Skip to content
https://basecamp.com

Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
87
GRADE
B
FIX
2
REVIEW
3
PASS
10
INFO
2

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
70
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

2.55 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

6.09 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

68 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.000

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

5.33 s

Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.

6.10 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
17
10 PASS 3 REVIEW 2 FIX
D
Page Weight Budget
Action
2.5 MB transferred, 116 requests
FIX
2.5 MB transferred, 116 requests
Warning::
Page weighs 2.7 MB (2.5 MB transferred)
Warning::
Images are 2.2 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 2.2 MB
Info::
Fonts are 222 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 222 KB
Warning::
116 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.53 g CO2 per page load
2.5 MB / 2.4 MB budget
2.5 MB transferred
116 requests
0.53 g CO2 per page load
Images 2.2 MiB 86%
Fonts 221.7 KiB 9%
CSS 55.2 KiB 2%
JavaScript 46.1 KiB 2%
HTML 24.1 KiB 1%
Other 14.8 KiB 1%
Other 2.5 KiB 0%
Other 491 B 0%
0 2.4 MB 4.9 MB
Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

D
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.
Info::
ETag present — enables conditional (304) responses
Info::
Last-Modified header present

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

B
Image Optimization
26 images, 0 KB saveable
REVIEW
26 images, 0 KB saveable
Warning::
https://basecamp.com/assets/images/home/illustrati... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
26 images 2.2 MB
0 oversized -0 KB
11 legacy format
1 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

B
JS Execution Cost
873ms total JS execution
REVIEW
873ms total JS execution
Warning::
Unattributable: 371ms CPU time
Warning::
https://basecamp.com/js/script.outbound-links.tagg...: 332ms CPU time
Info::
https://basecamp.com/: 112ms CPU time
Info::
https://basecamp.com/assets/js/script.js?v=1.0.6: 58ms CPU time
Info::
Third-party scripts: 371ms (42% of total)

Main Thread Breakdown

Other 47% Style & Layout 30% Script Evaluation 14% Rendering 4% Parse HTML & CSS 4%
ScriptTotalScriptingParse/CompileParty
Unattributable371ms56ms0ms3rd
https://basecamp.com/js/script.outbound-links.tagged-events.js332ms24ms1ms1st
https://basecamp.com/112ms8ms3ms1st
https://basecamp.com/assets/js/script.js?v=1.0.658ms44ms0ms1st
C
Page Weight Inventory
Action
116 resources · 2.5 MB · 0 KB savings available
REVIEW
116 resources · 2.5 MB · 0 KB savings available
Warning::
Page weight 1.5 MB over 1MB target
Got: 2.5 MB Expected: ≤ 1 MB
Info::
1 third-party resources (0% of weight)
Info::
2 resources over 200KB
116 resources · 2.5 MiB · 1 third-party 1.5 MiB over 1MB target
Image 86% · 2.2 MiB
Font 9% · 221.7 KiB
CSS 2% · 55.2 KiB
JavaScript 2% · 46.1 KiB
Document 1% · 24.1 KiB
Other 0% · 3.0 KiB
A+
Third-Party Impact
0% third-party, 0 ms blocking
PASS
0% third-party, 0 ms blocking
Info::
Third-party code accounts for 0% of page weight (2.5 KiB of 2.5 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
6 fonts (222 KB)
PASS
6 fonts (222 KB)
Info::
6 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

6

222 KB total

Render-blocking

0

of 6

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s FCP 2.5 s LCP 6.1 shttps://basecamp.com/assets/fonts/Graphik-Semibold-Web.woff2Graphik-Semibold-Web.woff2 https://basecamp.com/assets/fonts/Graphik-Semibold-Web.woff2 — 40.0 KiB — 152 ms — font-display: swaphttps://basecamp.com/assets/fonts/Graphik-Regular-Web.woff2Graphik-Regular-Web.woff2 https://basecamp.com/assets/fonts/Graphik-Regular-Web.woff2 — 35.8 KiB — 153 ms — font-display: swaphttps://basecamp.com/assets/fonts/Graphik-Medium-Web.woff2Graphik-Medium-Web.woff2 https://basecamp.com/assets/fonts/Graphik-Medium-Web.woff2 — 34.8 KiB — 134 ms — font-display: swaphttps://basecamp.com/assets/fonts/Graphik-Bold-Web.woff2Graphik-Bold-Web.woff2 https://basecamp.com/assets/fonts/Graphik-Bold-Web.woff2 — 37.0 KiB — 149 ms — font-display: swaphttps://basecamp.com/assets/fonts/Graphik-RegularItalic-Web.woff2Graphik-RegularItalic-W... https://basecamp.com/assets/fonts/Graphik-RegularItalic-Web.woff2 — 38.0 KiB — 163 ms — font-display: swaphttps://basecamp.com/assets/fonts/SharpiePro-Regular.woffSharpiePro-Regular.woff https://basecamp.com/assets/fonts/SharpiePro-Regular.woff — 36.1 KiB — 158 ms — font-display: swap
Graphik-Semibold-Web.woff2 woff2 swap
Size 40 KB
Load time 152 ms
Start 415 ms
Risk FOUT — text flashes from fallback to web font
Graphik-Regular-Web.woff2 woff2 swap
Size 36 KB
Load time 153 ms
Start 415 ms
Risk FOUT — text flashes from fallback to web font
Graphik-Medium-Web.woff2 woff2 swap
Size 35 KB
Load time 134 ms
Start 415 ms
Risk FOUT — text flashes from fallback to web font
Graphik-Bold-Web.woff2 woff2 swap
Size 37 KB
Load time 149 ms
Start 421 ms
Risk FOUT — text flashes from fallback to web font
Graphik-RegularItalic-W... woff2 swap
Size 38 KB
Load time 163 ms
Start 421 ms
Risk FOUT — text flashes from fallback to web font
SharpiePro-Regular.woff woff swap
Size 36 KB
Load time 158 ms
Start 422 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
Optimization checklist
  • Preload critical fonts (priority=high)
  • Use woff2 format for all fonts
  • Set font-display to swap, optional, or fallback
  • Subset large fonts (≤100 KB each)

Fixing the unchecked items could save ~11 KB and ~22 ms

A
JS Bundles
23 scripts, 0 KB unused
PASS
23 scripts, 0 KB unused
Warning::
https://basecamp.com/assets/js/packages/stimulus.j...: unminified — 6 KB could be saved
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://basecamp.com/assets/js/packages/cookie.js?v=1.0.61 KB—✓1st
https://basecamp.com/assets/js/application.js?v=1.0.61 KB—✓1st
https://basecamp.com/assets/js/script.js?v=1.0.61 KB—✓1st
https://basecamp.com/js/script.outbound-links.tagged-events.js3 KB—✓1st
https://basecamp.com/assets/js/packages/stimulus.js24 KB—✗1st
https://basecamp.com/assets/js/controllers/signup_controller.js1 KB—✓1st
https://basecamp.com/assets/js/controllers/signup_iframe_controller.js1 KB—✓1st
https://basecamp.com/assets/js/controllers/tracking_controller.js3 KB—✓1st
https://basecamp.com/assets/js/controllers/engaged_session_controller.js1 KB—✓1st
https://basecamp.com/assets/js/modules/body.js1 KB—✓1st
A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall
116 requests over 1689ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s FCP 2.5 s LCP 6.1 shttps://basecamp.com// https://basecamp.com/ — 200 — 24.1 KiB — 188 ms — h2https://basecamp.com/assets/css/reset.css?v=1.0.6/assets/css/reset.css?v=1.0.6 https://basecamp.com/assets/css/reset.css?v=1.0.6 — 200 — 866 B — 46 ms — h2https://basecamp.com/assets/css/root.css?v=1.0.6/assets/css/root.css?v=1.0.6 https://basecamp.com/assets/css/root.css?v=1.0.6 — 200 — 1.2 KiB — 47 ms — h2https://basecamp.com/assets/css/fonts.css?v=1.0.6/assets/css/fonts.css?v=1.0.6 https://basecamp.com/assets/css/fonts.css?v=1.0.6 — 200 — 600 B — 48 ms — h2https://basecamp.com/assets/css/base.css?v=1.0.6/assets/css/base.css?v=1.0.6 https://basecamp.com/assets/css/base.css?v=1.0.6 — 200 — 1.2 KiB — 52 ms — h2https://basecamp.com/assets/css/space.css?v=1.0.6/assets/css/space.css?v=1.0.6 https://basecamp.com/assets/css/space.css?v=1.0.6 — 200 — 306 B — 48 ms — h2https://basecamp.com/assets/css/apps.css?v=1.0.6/assets/css/apps.css?v=1.0.6 https://basecamp.com/assets/css/apps.css?v=1.0.6 — 200 — 266 B — 56 ms — h2https://basecamp.com/assets/css/blockquotes.css?v=1.0.6/assets/css/blockquotes.css?v=1.0.6 https://basecamp.com/assets/css/blockquotes.css?v=1.0.6 — 200 — 772 B — 54 ms — h2https://basecamp.com/assets/css/books.css?v=1.0.6/assets/css/books.css?v=1.0.6 https://basecamp.com/assets/css/books.css?v=1.0.6 — 200 — 1.0 KiB — 56 ms — h2https://basecamp.com/assets/css/bootstrapped.css?v=1.0.6/assets/css/bootstrapped.css?v=1.0.... https://basecamp.com/assets/css/bootstrapped.css?v=1.0.6 — 200 — 760 B — 58 ms — h2https://basecamp.com/assets/css/button.css?v=1.0.6/assets/css/button.css?v=1.0.6 https://basecamp.com/assets/css/button.css?v=1.0.6 — 200 — 803 B — 47 ms — h2https://basecamp.com/assets/css/buttons.css?v=1.0.6/assets/css/buttons.css?v=1.0.6 https://basecamp.com/assets/css/buttons.css?v=1.0.6 — 200 — 206 B — 48 ms — h2https://basecamp.com/assets/css/classes.css?v=1.0.6/assets/css/classes.css?v=1.0.6 https://basecamp.com/assets/css/classes.css?v=1.0.6 — 200 — 592 B — 50 ms — h2https://basecamp.com/assets/css/columns.css?v=1.0.6/assets/css/columns.css?v=1.0.6 https://basecamp.com/assets/css/columns.css?v=1.0.6 — 200 — 818 B — 55 ms — h2https://basecamp.com/assets/css/command.css?v=1.0.6/assets/css/command.css?v=1.0.6 https://basecamp.com/assets/css/command.css?v=1.0.6 — 200 — 1.1 KiB — 59 ms — h2https://basecamp.com/assets/css/data-classes.css?v=1.0.6/assets/css/data-classes.css?v=1.0.... https://basecamp.com/assets/css/data-classes.css?v=1.0.6 — 200 — 827 B — 58 ms — h2https://basecamp.com/assets/css/data-signups.css?v=1.0.6/assets/css/data-signups.css?v=1.0.... https://basecamp.com/assets/css/data-signups.css?v=1.0.6 — 200 — 609 B — 58 ms — h2https://basecamp.com/assets/css/details.css?v=1.0.6/assets/css/details.css?v=1.0.6 https://basecamp.com/assets/css/details.css?v=1.0.6 — 200 — 946 B — 55 ms — h2https://basecamp.com/assets/css/features.css?v=1.0.6/assets/css/features.css?v=1.0.6 https://basecamp.com/assets/css/features.css?v=1.0.6 — 200 — 1.3 KiB — 77 ms — h2https://basecamp.com/assets/css/footer.css?v=1.0.6/assets/css/footer.css?v=1.0.6 https://basecamp.com/assets/css/footer.css?v=1.0.6 — 200 — 1.6 KiB — 70 ms — h2https://basecamp.com/assets/css/frame.css?v=1.0.6/assets/css/frame.css?v=1.0.6 https://basecamp.com/assets/css/frame.css?v=1.0.6 — 200 — 254 B — 70 ms — h2https://basecamp.com/assets/css/headline.css?v=1.0.6/assets/css/headline.css?v=1.0.6 https://basecamp.com/assets/css/headline.css?v=1.0.6 — 200 — 1.3 KiB — 71 ms — h2https://basecamp.com/assets/css/help.css?v=1.0.6/assets/css/help.css?v=1.0.6 https://basecamp.com/assets/css/help.css?v=1.0.6 — 200 — 676 B — 73 ms — h2https://basecamp.com/assets/css/illustration.css?v=1.0.6/assets/css/illustration.css?v=1.0.... https://basecamp.com/assets/css/illustration.css?v=1.0.6 — 200 — 511 B — 75 ms — h2https://basecamp.com/assets/css/image.css?v=1.0.6/assets/css/image.css?v=1.0.6 https://basecamp.com/assets/css/image.css?v=1.0.6 — 200 — 703 B — 76 ms — h2https://basecamp.com/assets/css/integrations.css?v=1.0.6/assets/css/integrations.css?v=1.0.... https://basecamp.com/assets/css/integrations.css?v=1.0.6 — 200 — 1.0 KiB — 77 ms — h2https://basecamp.com/assets/css/intro.css?v=1.0.6/assets/css/intro.css?v=1.0.6 https://basecamp.com/assets/css/intro.css?v=1.0.6 — 200 — 678 B — 78 ms — h2https://basecamp.com/assets/css/jlmdmj.css?v=1.0.6/assets/css/jlmdmj.css?v=1.0.6 https://basecamp.com/assets/css/jlmdmj.css?v=1.0.6 — 200 — 2.2 KiB — 78 ms — h2https://basecamp.com/assets/css/learn.css?v=1.0.6/assets/css/learn.css?v=1.0.6 https://basecamp.com/assets/css/learn.css?v=1.0.6 — 200 — 1.2 KiB — 79 ms — h2https://basecamp.com/assets/css/letter.css?v=1.0.6/assets/css/letter.css?v=1.0.6 https://basecamp.com/assets/css/letter.css?v=1.0.6 — 200 — 1.2 KiB — 80 ms — h2
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s FCP 2.5 s LCP 6.1 shttps://basecamp.com// https://basecamp.com/ — 200 — 24.1 KiB — 188 ms — h2https://basecamp.com/assets/css/reset.css?v=1.0.6/assets/css/reset.css?v=1.0.6 https://basecamp.com/assets/css/reset.css?v=1.0.6 — 200 — 866 B — 46 ms — h2https://basecamp.com/assets/css/root.css?v=1.0.6/assets/css/root.css?v=1.0.6 https://basecamp.com/assets/css/root.css?v=1.0.6 — 200 — 1.2 KiB — 47 ms — h2https://basecamp.com/assets/css/fonts.css?v=1.0.6/assets/css/fonts.css?v=1.0.6 https://basecamp.com/assets/css/fonts.css?v=1.0.6 — 200 — 600 B — 48 ms — h2https://basecamp.com/assets/css/base.css?v=1.0.6/assets/css/base.css?v=1.0.6 https://basecamp.com/assets/css/base.css?v=1.0.6 — 200 — 1.2 KiB — 52 ms — h2https://basecamp.com/assets/css/space.css?v=1.0.6/assets/css/space.css?v=1.0.6 https://basecamp.com/assets/css/space.css?v=1.0.6 — 200 — 306 B — 48 ms — h2https://basecamp.com/assets/css/apps.css?v=1.0.6/assets/css/apps.css?v=1.0.6 https://basecamp.com/assets/css/apps.css?v=1.0.6 — 200 — 266 B — 56 ms — h2https://basecamp.com/assets/css/blockquotes.css?v=1.0.6/assets/css/blockquotes.css?v=1.0.6 https://basecamp.com/assets/css/blockquotes.css?v=1.0.6 — 200 — 772 B — 54 ms — h2https://basecamp.com/assets/css/books.css?v=1.0.6/assets/css/books.css?v=1.0.6 https://basecamp.com/assets/css/books.css?v=1.0.6 — 200 — 1.0 KiB — 56 ms — h2https://basecamp.com/assets/css/bootstrapped.css?v=1.0.6/assets/css/bootstrapped.css?v=1.0.... https://basecamp.com/assets/css/bootstrapped.css?v=1.0.6 — 200 — 760 B — 58 ms — h2https://basecamp.com/assets/css/button.css?v=1.0.6/assets/css/button.css?v=1.0.6 https://basecamp.com/assets/css/button.css?v=1.0.6 — 200 — 803 B — 47 ms — h2https://basecamp.com/assets/css/buttons.css?v=1.0.6/assets/css/buttons.css?v=1.0.6 https://basecamp.com/assets/css/buttons.css?v=1.0.6 — 200 — 206 B — 48 ms — h2https://basecamp.com/assets/css/classes.css?v=1.0.6/assets/css/classes.css?v=1.0.6 https://basecamp.com/assets/css/classes.css?v=1.0.6 — 200 — 592 B — 50 ms — h2https://basecamp.com/assets/css/columns.css?v=1.0.6/assets/css/columns.css?v=1.0.6 https://basecamp.com/assets/css/columns.css?v=1.0.6 — 200 — 818 B — 55 ms — h2https://basecamp.com/assets/css/command.css?v=1.0.6/assets/css/command.css?v=1.0.6 https://basecamp.com/assets/css/command.css?v=1.0.6 — 200 — 1.1 KiB — 59 ms — h2https://basecamp.com/assets/css/data-classes.css?v=1.0.6/assets/css/data-classes.css?v=1.0.... https://basecamp.com/assets/css/data-classes.css?v=1.0.6 — 200 — 827 B — 58 ms — h2https://basecamp.com/assets/css/data-signups.css?v=1.0.6/assets/css/data-signups.css?v=1.0.... https://basecamp.com/assets/css/data-signups.css?v=1.0.6 — 200 — 609 B — 58 ms — h2https://basecamp.com/assets/css/details.css?v=1.0.6/assets/css/details.css?v=1.0.6 https://basecamp.com/assets/css/details.css?v=1.0.6 — 200 — 946 B — 55 ms — h2https://basecamp.com/assets/css/features.css?v=1.0.6/assets/css/features.css?v=1.0.6 https://basecamp.com/assets/css/features.css?v=1.0.6 — 200 — 1.3 KiB — 77 ms — h2https://basecamp.com/assets/css/footer.css?v=1.0.6/assets/css/footer.css?v=1.0.6 https://basecamp.com/assets/css/footer.css?v=1.0.6 — 200 — 1.6 KiB — 70 ms — h2https://basecamp.com/assets/css/frame.css?v=1.0.6/assets/css/frame.css?v=1.0.6 https://basecamp.com/assets/css/frame.css?v=1.0.6 — 200 — 254 B — 70 ms — h2https://basecamp.com/assets/css/headline.css?v=1.0.6/assets/css/headline.css?v=1.0.6 https://basecamp.com/assets/css/headline.css?v=1.0.6 — 200 — 1.3 KiB — 71 ms — h2https://basecamp.com/assets/css/help.css?v=1.0.6/assets/css/help.css?v=1.0.6 https://basecamp.com/assets/css/help.css?v=1.0.6 — 200 — 676 B — 73 ms — h2https://basecamp.com/assets/css/illustration.css?v=1.0.6/assets/css/illustration.css?v=1.0.... https://basecamp.com/assets/css/illustration.css?v=1.0.6 — 200 — 511 B — 75 ms — h2https://basecamp.com/assets/css/image.css?v=1.0.6/assets/css/image.css?v=1.0.6 https://basecamp.com/assets/css/image.css?v=1.0.6 — 200 — 703 B — 76 ms — h2https://basecamp.com/assets/css/integrations.css?v=1.0.6/assets/css/integrations.css?v=1.0.... https://basecamp.com/assets/css/integrations.css?v=1.0.6 — 200 — 1.0 KiB — 77 ms — h2https://basecamp.com/assets/css/intro.css?v=1.0.6/assets/css/intro.css?v=1.0.6 https://basecamp.com/assets/css/intro.css?v=1.0.6 — 200 — 678 B — 78 ms — h2https://basecamp.com/assets/css/jlmdmj.css?v=1.0.6/assets/css/jlmdmj.css?v=1.0.6 https://basecamp.com/assets/css/jlmdmj.css?v=1.0.6 — 200 — 2.2 KiB — 78 ms — h2https://basecamp.com/assets/css/learn.css?v=1.0.6/assets/css/learn.css?v=1.0.6 https://basecamp.com/assets/css/learn.css?v=1.0.6 — 200 — 1.2 KiB — 79 ms — h2https://basecamp.com/assets/css/letter.css?v=1.0.6/assets/css/letter.css?v=1.0.6 https://basecamp.com/assets/css/letter.css?v=1.0.6 — 200 — 1.2 KiB — 80 ms — h2https://basecamp.com/assets/css/main.css?v=1.0.6/assets/css/main.css?v=1.0.6 https://basecamp.com/assets/css/main.css?v=1.0.6 — 200 — 278 B — 81 ms — h2https://basecamp.com/assets/css/marquee.css?v=1.0.6/assets/css/marquee.css?v=1.0.6 https://basecamp.com/assets/css/marquee.css?v=1.0.6 — 200 — 686 B — 82 ms — h2https://basecamp.com/assets/css/modal-trigger.css?v=1.0.6/assets/css/modal-trigger.css?v=1.0... https://basecamp.com/assets/css/modal-trigger.css?v=1.0.6 — 200 — 416 B — 83 ms — h2https://basecamp.com/assets/css/modal.css?v=1.0.6/assets/css/modal.css?v=1.0.6 https://basecamp.com/assets/css/modal.css?v=1.0.6 — 200 — 1.1 KiB — 84 ms — h2https://basecamp.com/assets/css/nav-basic.css?v=1.0.6/assets/css/nav-basic.css?v=1.0.6 https://basecamp.com/assets/css/nav-basic.css?v=1.0.6 — 200 — 794 B — 84 ms — h2https://basecamp.com/assets/css/nav.css?v=1.0.6/assets/css/nav.css?v=1.0.6 https://basecamp.com/assets/css/nav.css?v=1.0.6 — 200 — 1.7 KiB — 85 ms — h2https://basecamp.com/assets/css/new.css?v=1.0.6/assets/css/new.css?v=1.0.6 https://basecamp.com/assets/css/new.css?v=1.0.6 — 200 — 1.4 KiB — 86 ms — h2https://basecamp.com/assets/css/newsletter-archive.css?v=1.0.6/assets/css/newsletter-archive.css?... https://basecamp.com/assets/css/newsletter-archive.css?v=1.0.6 — 200 — 617 B — 87 ms — h2https://basecamp.com/assets/css/newsletter.css?v=1.0.6/assets/css/newsletter.css?v=1.0.6 https://basecamp.com/assets/css/newsletter.css?v=1.0.6 — 200 — 1.2 KiB — 88 ms — h2https://basecamp.com/assets/css/path.css?v=1.0.6/assets/css/path.css?v=1.0.6 https://basecamp.com/assets/css/path.css?v=1.0.6 — 200 — 2.5 KiB — 89 ms — h2https://basecamp.com/assets/css/paths-feature.css?v=1.0.6/assets/css/paths-feature.css?v=1.0... https://basecamp.com/assets/css/paths-feature.css?v=1.0.6 — 200 — 1.7 KiB — 90 ms — h2https://basecamp.com/assets/css/paths-nav.css?v=1.0.6/assets/css/paths-nav.css?v=1.0.6 https://basecamp.com/assets/css/paths-nav.css?v=1.0.6 — 200 — 2.1 KiB — 91 ms — h2https://basecamp.com/assets/css/paths.css?v=1.0.6/assets/css/paths.css?v=1.0.6 https://basecamp.com/assets/css/paths.css?v=1.0.6 — 200 — 858 B — 91 ms — h2https://basecamp.com/assets/css/pricing.css?v=1.0.6/assets/css/pricing.css?v=1.0.6 https://basecamp.com/assets/css/pricing.css?v=1.0.6 — 200 — 1.9 KiB — 92 ms — h2https://basecamp.com/assets/css/prose.css?v=1.0.6/assets/css/prose.css?v=1.0.6 https://basecamp.com/assets/css/prose.css?v=1.0.6 — 200 — 800 B — 93 ms — h2https://basecamp.com/assets/css/roadblock.css?v=1.0.6/assets/css/roadblock.css?v=1.0.6 https://basecamp.com/assets/css/roadblock.css?v=1.0.6 — 200 — 1.0 KiB — 94 ms — h2https://basecamp.com/assets/css/scroll-snap.css?v=1.0.6/assets/css/scroll-snap.css?v=1.0.6 https://basecamp.com/assets/css/scroll-snap.css?v=1.0.6 — 200 — 737 B — 95 ms — h2https://basecamp.com/assets/css/statement.css?v=1.0.6/assets/css/statement.css?v=1.0.6 https://basecamp.com/assets/css/statement.css?v=1.0.6 — 200 — 1.3 KiB — 97 ms — h2https://basecamp.com/assets/css/support.css?v=1.0.6/assets/css/support.css?v=1.0.6 https://basecamp.com/assets/css/support.css?v=1.0.6 — 200 — 1.4 KiB — 95 ms — h2https://basecamp.com/assets/css/target.css?v=1.0.6/assets/css/target.css?v=1.0.6 https://basecamp.com/assets/css/target.css?v=1.0.6 — 200 — 275 B — 96 ms — h2https://basecamp.com/assets/css/testimonials.css?v=1.0.6/assets/css/testimonials.css?v=1.0.... https://basecamp.com/assets/css/testimonials.css?v=1.0.6 — 200 — 1.0 KiB — 98 ms — h2https://basecamp.com/assets/css/tracking.css?v=1.0.6/assets/css/tracking.css?v=1.0.6 https://basecamp.com/assets/css/tracking.css?v=1.0.6 — 200 — 847 B — 97 ms — h2https://basecamp.com/assets/css/type.css?v=1.0.6/assets/css/type.css?v=1.0.6 https://basecamp.com/assets/css/type.css?v=1.0.6 — 200 — 1.0 KiB — 104 ms — h2https://basecamp.com/assets/css/video-inline.css?v=1.0.6/assets/css/video-inline.css?v=1.0.... https://basecamp.com/assets/css/video-inline.css?v=1.0.6 — 200 — 871 B — 102 ms — h2https://basecamp.com/assets/css/video.css?v=1.0.6/assets/css/video.css?v=1.0.6 https://basecamp.com/assets/css/video.css?v=1.0.6 — 200 — 886 B — 99 ms — h2https://basecamp.com/assets/css/visual.css?v=1.0.6/assets/css/visual.css?v=1.0.6 https://basecamp.com/assets/css/visual.css?v=1.0.6 — 200 — 1.5 KiB — 101 ms — h2https://basecamp.com/assets/css/yes-label.css?v=1.0.6/assets/css/yes-label.css?v=1.0.6 https://basecamp.com/assets/css/yes-label.css?v=1.0.6 — 200 — 461 B — 99 ms — h2https://basecamp.com/assets/css/yes.css?v=1.0.6/assets/css/yes.css?v=1.0.6 https://basecamp.com/assets/css/yes.css?v=1.0.6 — 200 — 933 B — 104 ms — h2https://basecamp.com/assets/js/packages/cookie.js?v=1.0.6/assets/js/packages/cookie.js?v=1.0... https://basecamp.com/assets/js/packages/cookie.js?v=1.0.6 — 200 — 980 B — 105 ms — h2https://basecamp.com/assets/js/application.js?v=1.0.6/assets/js/application.js?v=1.0.6 https://basecamp.com/assets/js/application.js?v=1.0.6 — 200 — 737 B — 107 ms — h2https://basecamp.com/assets/js/script.js?v=1.0.6/assets/js/script.js?v=1.0.6 https://basecamp.com/assets/js/script.js?v=1.0.6 — 200 — 526 B — 108 ms — h2https://basecamp.com/assets/images/home/illustration-mobile.png/assets/images/home/illustration-mo... https://basecamp.com/assets/images/home/illustration-mobile.png — 200 — 373.3 KiB — 124 ms — h2https://basecamp.com/videos/home/walkthrough-small.webp/videos/home/walkthrough-small.webp https://basecamp.com/videos/home/walkthrough-small.webp — 200 — 154.4 KiB — 127 ms — h2https://basecamp.com/js/script.outbound-links.tagged-events.js/js/script.outbound-links.tagged-ev... https://basecamp.com/js/script.outbound-links.tagged-events.js — 200 — 2.9 KiB — 28 ms — h2https://basecamp.com/assets/js/packages/stimulus.js/assets/js/packages/stimulus.js https://basecamp.com/assets/js/packages/stimulus.js — 200 — 23.7 KiB — 56 ms — h2https://basecamp.com/assets/js/controllers/signup_controller.js/assets/js/controllers/signup_contr... https://basecamp.com/assets/js/controllers/signup_controller.js — 200 — 1.1 KiB — 34 ms — h2https://basecamp.com/assets/js/controllers/signup_iframe_controller.js/assets/js/controllers/signup_ifram... https://basecamp.com/assets/js/controllers/signup_iframe_controller.js — 200 — 768 B — 29 ms — h2https://basecamp.com/assets/js/controllers/tracking_controller.js/assets/js/controllers/tracking_con... https://basecamp.com/assets/js/controllers/tracking_controller.js — 200 — 2.8 KiB — 32 ms — h2https://basecamp.com/assets/js/controllers/engaged_session_controller.js/assets/js/controllers/engaged_sess... https://basecamp.com/assets/js/controllers/engaged_session_controller.js — 200 — 935 B — 33 ms — h2https://basecamp.com/assets/js/modules/body.js/assets/js/modules/body.js https://basecamp.com/assets/js/modules/body.js — 200 — 939 B — 34 ms — h2https://basecamp.com/assets/js/modules/cancel.js/assets/js/modules/cancel.js https://basecamp.com/assets/js/modules/cancel.js — 200 — 724 B — 35 ms — h2https://basecamp.com/assets/js/modules/classes.js/assets/js/modules/classes.js https://basecamp.com/assets/js/modules/classes.js — 200 — 1.4 KiB — 37 ms — h2https://basecamp.com/assets/js/modules/command.js/assets/js/modules/command.js https://basecamp.com/assets/js/modules/command.js — 200 — 595 B — 36 ms — h2https://basecamp.com/assets/js/modules/details.js/assets/js/modules/details.js https://basecamp.com/assets/js/modules/details.js — 200 — 638 B — 43 ms — h2https://basecamp.com/assets/js/modules/jlmdmj.js/assets/js/modules/jlmdmj.js https://basecamp.com/assets/js/modules/jlmdmj.js — 200 — 942 B — 44 ms — h2https://basecamp.com/assets/js/modules/modal.js/assets/js/modules/modal.js https://basecamp.com/assets/js/modules/modal.js — 200 — 1.7 KiB — 56 ms — h2https://basecamp.com/assets/js/modules/nav.js/assets/js/modules/nav.js https://basecamp.com/assets/js/modules/nav.js — 200 — 1.1 KiB — 37 ms — h2https://basecamp.com/assets/js/modules/newsletter.js/assets/js/modules/newsletter.js https://basecamp.com/assets/js/modules/newsletter.js — 200 — 681 B — 47 ms — h2https://basecamp.com/assets/js/modules/paths.js/assets/js/modules/paths.js https://basecamp.com/assets/js/modules/paths.js — 200 — 991 B — 41 ms — h2https://basecamp.com/assets/js/modules/scrollSnap.js/assets/js/modules/scrollSnap.js https://basecamp.com/assets/js/modules/scrollSnap.js — 200 — 676 B — 145 ms — h2https://basecamp.com/assets/js/modules/signups.js/assets/js/modules/signups.js https://basecamp.com/assets/js/modules/signups.js — 200 — 678 B — 43 ms — h2https://basecamp.com/assets/js/modules/target.js/assets/js/modules/target.js https://basecamp.com/assets/js/modules/target.js — 200 — 389 B — 54 ms — h2https://basecamp.com/assets/js/modules/video.js/assets/js/modules/video.js https://basecamp.com/assets/js/modules/video.js — 200 — 625 B — 52 ms — h2https://basecamp.com/assets/images/general/jf-signature.svg/assets/images/general/jf-signature... https://basecamp.com/assets/images/general/jf-signature.svg — 200 — 6.6 KiB — 69 ms — h2https://basecamp.com/assets/images/general/icon-play.svg/assets/images/general/icon-play.sv... https://basecamp.com/assets/images/general/icon-play.svg — 200 — 430 B — 49 ms — h2https://basecamp.com/assets/images/general/icon-checkmark.svg/assets/images/general/icon-checkma... https://basecamp.com/assets/images/general/icon-checkmark.svg — 200 — 963 B — 47 ms — h2https://basecamp.com/assets/images/general/icon-details.svg/assets/images/general/icon-details... https://basecamp.com/assets/images/general/icon-details.svg — 200 — 770 B — 52 ms — h2https://basecamp.com/assets/images/general/stars.svg/assets/images/general/stars.svg https://basecamp.com/assets/images/general/stars.svg — 200 — 1.7 KiB — 51 ms — h2https://basecamp.com/assets/images/general/icon-apple.svg/assets/images/general/icon-apple.s... https://basecamp.com/assets/images/general/icon-apple.svg — 200 — 912 B — 49 ms — h2https://basecamp.com/assets/images/general/icon-windows.svg/assets/images/general/icon-windows... https://basecamp.com/assets/images/general/icon-windows.svg — 200 — 426 B — 53 ms — h2https://basecamp.com/assets/images/general/icon-android.svg/assets/images/general/icon-android... https://basecamp.com/assets/images/general/icon-android.svg — 200 — 2.3 KiB — 55 ms — h2https://basecamp.com/assets/images/general/icon-basecamp.svg/assets/images/general/icon-basecam... https://basecamp.com/assets/images/general/icon-basecamp.svg — 200 — 1.5 KiB — 54 ms — h2https://basecamp.com/assets/images/general/icon-hey.svg/assets/images/general/icon-hey.svg https://basecamp.com/assets/images/general/icon-hey.svg — 200 — 1.8 KiB — 52 ms — h2https://basecamp.com/api/event/api/event https://basecamp.com/api/event — 202 — 491 B — 1.3 s — h2https://basecamp.com/assets/fonts/Graphik-Semibold-Web.woff2/assets/fonts/Graphik-Semibold-Web.... https://basecamp.com/assets/fonts/Graphik-Semibold-Web.woff2 — 200 — 40.0 KiB — 152 ms — h2https://basecamp.com/assets/fonts/Graphik-Regular-Web.woff2/assets/fonts/Graphik-Regular-Web.w... https://basecamp.com/assets/fonts/Graphik-Regular-Web.woff2 — 200 — 35.8 KiB — 153 ms — h2https://basecamp.com/assets/fonts/Graphik-Medium-Web.woff2/assets/fonts/Graphik-Medium-Web.wo... https://basecamp.com/assets/fonts/Graphik-Medium-Web.woff2 — 200 — 34.8 KiB — 134 ms — h2https://basecamp.com/assets/fonts/Graphik-Bold-Web.woff2/assets/fonts/Graphik-Bold-Web.woff... https://basecamp.com/assets/fonts/Graphik-Bold-Web.woff2 — 200 — 37.0 KiB — 149 ms — h2https://basecamp.com/assets/fonts/Graphik-RegularItalic-Web.woff2/assets/fonts/Graphik-RegularItalic... https://basecamp.com/assets/fonts/Graphik-RegularItalic-Web.woff2 — 200 — 38.0 KiB — 163 ms — h2https://basecamp.com/assets/fonts/SharpiePro-Regular.woff/assets/fonts/SharpiePro-Regular.wo... https://basecamp.com/assets/fonts/SharpiePro-Regular.woff — 200 — 36.1 KiB — 158 ms — h2https://dash.37signals.com/support/classes/export.jsondash.37signals.com/support/classes/... https://dash.37signals.com/support/classes/export.json — 200 — 2.5 KiB — 376 ms — h2https://basecamp.com/assets/images/general/favicon.ico/assets/images/general/favicon.ico https://basecamp.com/assets/images/general/favicon.ico — 200 — 14.8 KiB — 25 ms — h2https://basecamp.com/videos/home/whats-my-week-look-like.webp/videos/home/whats-my-week-look-lik... https://basecamp.com/videos/home/whats-my-week-look-like.webp — 200 — 33.7 KiB — 32 ms — h2https://basecamp.com/videos/home/whats-on-my-plate-today.webp/videos/home/whats-on-my-plate-toda... https://basecamp.com/videos/home/whats-on-my-plate-today.webp — 200 — 62.1 KiB — 43 ms — h2https://basecamp.com/videos/home/which-projects-am-i-on.webp/videos/home/which-projects-am-i-on... https://basecamp.com/videos/home/which-projects-am-i-on.webp — 200 — 234.6 KiB — 43 ms — h2https://basecamp.com/videos/home/all-in-one-toolbox.webp/videos/home/all-in-one-toolbox.web... https://basecamp.com/videos/home/all-in-one-toolbox.webp — 200 — 166.0 KiB — 45 ms — h2https://basecamp.com/assets/images/screenshots/to-dos-thumbnail.webp/assets/images/screenshots/to-dos-t... https://basecamp.com/assets/images/screenshots/to-dos-thumbnail.webp — 200 — 90.7 KiB — 45 ms — h2https://basecamp.com/assets/images/screenshots/message-board-thumbnail.webp/assets/images/screenshots/message-... https://basecamp.com/assets/images/screenshots/message-board-thumbnail.webp — 200 — 130.2 KiB — 51 ms — h2https://basecamp.com/assets/images/screenshots/schedule-thumbnail.webp/assets/images/screenshots/schedule... https://basecamp.com/assets/images/screenshots/schedule-thumbnail.webp — 200 — 73.2 KiB — 46 ms — h2https://basecamp.com/assets/images/screenshots/docs-and-files-thumbnail.webp/assets/images/screenshots/docs-and... https://basecamp.com/assets/images/screenshots/docs-and-files-thumbnail.webp — 200 — 161.7 KiB — 55 ms — h2https://basecamp.com/assets/images/screenshots/chat-thumbnail.webp/assets/images/screenshots/chat-thu... https://basecamp.com/assets/images/screenshots/chat-thumbnail.webp — 200 — 189.6 KiB — 58 ms — h2https://basecamp.com/assets/images/screenshots/card-table-thumbnail.webp/assets/images/screenshots/card-tab... https://basecamp.com/assets/images/screenshots/card-table-thumbnail.webp — 200 — 143.4 KiB — 61 ms — h2https://basecamp.com/videos/home/whats-overdue.webp/videos/home/whats-overdue.webp https://basecamp.com/videos/home/whats-overdue.webp — 200 — 73.6 KiB — 61 ms — h2https://basecamp.com/videos/home/how-much-time-have-we-spent.webp/videos/home/how-much-time-have-we-... https://basecamp.com/videos/home/how-much-time-have-we-spent.webp — 200 — 53.8 KiB — 61 ms — h2https://basecamp.com/videos/home/whos-responsible-for-what.webp/videos/home/whos-responsible-for-w... https://basecamp.com/videos/home/whos-responsible-for-what.webp — 200 — 68.9 KiB — 63 ms — h2https://basecamp.com/videos/home/whats-actually-been-happening.webp/videos/home/whats-actually-been-ha... https://basecamp.com/videos/home/whats-actually-been-happening.webp — 200 — 179.1 KiB — 65 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
42% of JavaScript execution is third-party
First-party Third-party 371ms · 0KB · $5/mo
Unattributable
Other
Costly
Execution 371ms
Transfer 0 KB
Monthly Cost $5/mo

These scripts may cost more than they're worth

  • Unattributable adds 371ms and costs ~$5/month

42% of JavaScript execution time comes from third-party scripts.

Why this matters

Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.

Learn more ▾

Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.

Source: web.dev / HTTP Archive Web Almanac

Unattributable takes 371ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

Send Feedback