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Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
93
GRADE
A
FIX
1
REVIEW
1
PASS
13
INFO
2

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

Mobile Desktop
89
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
79
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
96
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
83
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.

2.88 s

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

3.03 s

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

0 ms

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

0.045

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

2.97 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.

3.03 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
13 PASS 1 REVIEW 1 FIX
D
Third-Party Impact
Action
89% third-party, 0 ms blocking
FIX
89% third-party, 0 ms blocking
Warning::
Third-party code accounts for 89% of page weight (142.4 KiB of 159.8 KiB)
Info::
Third-party blocking time is low (0 ms)
89%
First-party Third-party
B
Image Optimization
2 images, 0 KB saveable
REVIEW
2 images, 0 KB saveable
Warning::
https://dx.doi.org/static/images/logos/footer_logo... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://dx.doi.org/static/images/logos/header_logo... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
2 images 5 KB
0 oversized -0 KB
2 legacy format
2 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

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

A+
Page Weight Budget
160 KB transferred, 13 requests
PASS
160 KB transferred, 13 requests
Info::
Page weighs 393 KB (160 KB transferred)
Info::
13 HTTP requests
Info::
Estimated 0.03 g CO2 per page load
160 KB / 2.4 MB budget
160 KB transferred
13 requests
0.03 g CO2 per page load
Fonts 90.3 KiB 57%
CSS 36.0 KiB 23%
JavaScript 23.8 KiB 15%
Images 4.9 KiB 3%
HTML 2.6 KiB 2%
Other 2.2 KiB 1%
0 2.4 MB 4.9 MB
Under budget
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+
JS Execution Cost
330ms total JS execution
PASS
330ms total JS execution
Info::
https://dx.doi.org/: 180ms CPU time
Info::
Unattributable: 150ms CPU time
Info::
Third-party scripts: 150ms (45% of total)

Main Thread Breakdown

Other 43% Style & Layout 38% Script Evaluation 7% Parse HTML & CSS 6%
ScriptTotalScriptingParse/CompileParty
https://dx.doi.org/180ms4ms1ms1st
Unattributable150ms7ms0ms3rd
A+
Font Loading
2 fonts (90 KB)
PASS
2 fonts (90 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

90 KB total

Render-blocking

0

of 2

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 FCP 2.9 s LCP 3.0 shttps://use.typekit.net/af/053fc9/00000000000000003b9af1e4/27/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3l https://use.typekit.net/af/053fc9/00000000000000003b9af1e4/27/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3 — 39.8 KiB — 10 ms — font-display: swaphttps://use.typekit.net/af/9b05f3/000000000000000000013365/27/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3l https://use.typekit.net/af/9b05f3/000000000000000000013365/27/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3 — 50.6 KiB — 12 ms — font-display: swap
l woff2 swap
Size 40 KB
Load time 10 ms
Start 278 ms
Risk FOUT — text flashes from fallback to web font
l woff2 swap
Size 51 KB
Load time 12 ms
Start 279 ms
Risk FOUT — text flashes from fallback to web font
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)
A+
JS Bundles
2 scripts, 0 KB unused
PASS
2 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/js/bootstrap.bundle.min.js23 KB—✓3rd
https://kit.fontawesome.com/731b8140c4.js0 KB—✓3rd
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
Page Weight Inventory
13 resources · 160 KB · 0 KB savings available
PASS
13 resources · 160 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 160 KB
Warning::
8 third-party resources (89% of weight)
13 resources · 159.8 KiB · 8 third-party Within 1MB page-weight target
Font 57% · 90.3 KiB
CSS 23% · 36.0 KiB
JavaScript 15% · 23.8 KiB
Image 4% · 7.1 KiB
Document 2% · 2.6 KiB
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

A+
HTTP Caching
max-age=14400 (4 hours)
PASS
max-age=14400 (4 hours)
Info::
Cache-Control header is set
Got: max-age=14400
Info::
Effective TTL: 4 hours (max-age=14400)
Info::
Last-Modified header present
Cache-Control

max-age=14400

DirectiveValueMeaning
max-age14400Cache for 4 hours
Effective TTL: 14400 seconds
Network Waterfall
13 requests over 292ms
INFO
0 ms 1.0 s 2.0 s 3.0 s FCP 2.9 s LCP 3.0 shttps://dx.doi.org// https://dx.doi.org/ — 200 — 2.6 KiB — 18 ms — h3https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.csscdn.jsdelivr.net/npm/bootstrap@5.0.... https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css — 200 — 25.2 KiB — 33 ms — h2https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/js/bootstrap.bundle.min.jscdn.jsdelivr.net/npm/bootstrap@5.0.... https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/js/bootstrap.bundle.min.js — 200 — 23.5 KiB — 31 ms — h2https://kit.fontawesome.com/731b8140c4.jskit.fontawesome.com/731b8140c4.js https://kit.fontawesome.com/731b8140c4.js — 403 — 292 B — 185 ms — h2https://dx.doi.org/static/css/style.css/static/css/style.css https://dx.doi.org/static/css/style.css — 200 — 7.7 KiB — 11 ms — h3https://fonts.googleapis.com/css2?family=Roboto+Mono&family=Roboto:wght@100&display=swapfonts.googleapis.com/css2?family=Ro... https://fonts.googleapis.com/css2?family=Roboto+Mono&family=Roboto:wght@100&display=swap — 200 — 2.1 KiB — 128 ms — h2https://dx.doi.org/static/images/logos/header_logo_cropped.svg/static/images/logos/header_logo_cr... https://dx.doi.org/static/images/logos/header_logo_cropped.svg — 200 — 2.5 KiB — 15 ms — h3https://dx.doi.org/static/images/logos/footer_logo_cropped.svg/static/images/logos/footer_logo_cr... https://dx.doi.org/static/images/logos/footer_logo_cropped.svg — 200 — 2.5 KiB — 17 ms — h3https://use.typekit.net/gcr6xms.cssuse.typekit.net/gcr6xms.css https://use.typekit.net/gcr6xms.css — 200 — 920 B — 12 ms — h2https://p.typekit.net/p.css?s=1&k=gcr6xms&ht=tk&f=10884.32874&a=12362348&app=typekit&e=cssp.typekit.net/p.css?s=1&k=gcr6xms&h... https://p.typekit.net/p.css?s=1&k=gcr6xms&ht=tk&f=10884.32874&a=12362348&app=typekit&e=css — 200 — 172 B — 18 ms — h2https://use.typekit.net/af/053fc9/00000000000000003b9af1e4/27/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3use.typekit.net/af/053fc9/000000000... https://use.typekit.net/af/053fc9/00000000000000003b9af1e4/27/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n7&v=3 — 200 — 39.8 KiB — 10 ms — h2https://use.typekit.net/af/9b05f3/000000000000000000013365/27/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3use.typekit.net/af/9b05f3/000000000... https://use.typekit.net/af/9b05f3/000000000000000000013365/27/l?primer=7cdcb44be4a7db8877ffa5c0007b8dd865b3bbc383831fe2ea177f62257a9191&fvd=n4&v=3 — 200 — 50.6 KiB — 12 ms — h2https://dx.doi.org/static/images/favicons/favicon-32x32.png/static/images/favicons/favicon-32x... https://dx.doi.org/static/images/favicons/favicon-32x32.png — 200 — 2.2 KiB — 11 ms — h3
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
45% of JavaScript execution is third-party
First-party Third-party 150ms · 0KB · $2/mo
Unattributable
Other
Optional
Execution 150ms
Transfer 0 KB
Monthly Cost $2/mo

45% 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

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.

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