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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
79
GRADE
C
FIX
1
REVIEW
4
PASS
7
INFO
2

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

Mobile Desktop
92
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
73
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.
77
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.

985 ms

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

1.44 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.

0.021

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

1.67 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.

1.62 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
14
7 PASS 4 REVIEW 1 FIX
F
Page Weight Budget
Action
2.9 MB transferred, 126 requests
FIX
2.9 MB transferred, 126 requests
Warning::
Page weighs 5.2 MB (2.9 MB transferred)
Warning::
Images are 1.8 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.8 MB
Warning::
JavaScript is 792 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 792 KB
Info::
Fonts are 215 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 215 KB
Warning::
126 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.60 g CO2 per page load
2.9 MB / 2.4 MB budget
2.9 MB transferred
126 requests
0.60 g CO2 per page load
Images 1.8 MiB 63%
JavaScript 791.8 KiB 27%
Fonts 215.0 KiB 7%
Other 24.0 KiB 1%
HTML 23.1 KiB 1%
CSS 20.8 KiB 1%
Other 10.3 KiB 0%
Other 7.8 KiB 0%
Other 0 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

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

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

C
Image Optimization
Action
51 images, 0 KB saveable
REVIEW
51 images, 0 KB saveable
Warning::
https://www.linuxfoundation.org/hubfs/cncf-color-3... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.linuxfoundation.org/hubfs/Tux-flat-ver... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.linuxfoundation.org/hubfs/LF%20Logo%20... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.linuxfoundation.org/hubfs/openssf-hori... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.linuxfoundation.org/hubfs/lfnetworking... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.linuxfoundation.org/hubfs/OpenJS%20Log... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.linuxfoundation.org/hs-fs/hubfs/DSC_80... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.linuxfoundation.org/hubfs/finos-horizo... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
51 images 1.8 MB
0 oversized -0 KB
35 legacy format
8 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

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

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

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

C
JS Execution Cost
Action
1344ms total JS execution
REVIEW
1344ms total JS execution
Warning::
Unattributable: 393ms CPU time
Warning::
https://www.linuxfoundation.org/: 388ms CPU time
Info::
https://cmp.osano.com/16A0DbT9yDNIaQkvZ/af2b9f1f-3...: 213ms CPU time
Info::
https://cdnjs.cloudflare.com/ajax/libs/jquery/3.7....: 127ms CPU time
Info::
https://www.linuxfoundation.org/_hcms/forms/v2.js: 80ms CPU time
Warning::
Third-party scripts: 877ms (65% of total)

Main Thread Breakdown

Script Evaluation 39% Other 30% Style & Layout 17% Rendering 5% Script Parsing & Compilation 5%
ScriptTotalScriptingParse/CompileParty
Unattributable393ms57ms0ms3rd
https://www.linuxfoundation.org/388ms12ms2ms1st
https://cmp.osano.com/16A0DbT9yDNIaQkvZ/af2b9f1f-3ac7-4a18-a99a-e487d04f08e6/osano.js213ms182ms4ms3rd
https://cdnjs.cloudflare.com/ajax/libs/jquery/3.7.1/jquery.min.js127ms69ms4ms3rd
https://www.linuxfoundation.org/_hcms/forms/v2.js80ms62ms15ms1st
https://www.googletagmanager.com/gtag/js?id=G-FBYHX832ZD&cx=c&gtm=4e646077ms65ms12ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-WWBXMJK66ms55ms10ms3rd
C
JS Bundles
Action
37 scripts, 231 KB unused
REVIEW
37 scripts, 231 KB unused
Warning::
https://www.linuxfoundation.org/_hcms/forms/v2.js: 77 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-FBYH...: 65 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-WWB...: 62 KB unused (46%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://lfx-segment.platform.linuxfoundation.org/l...: 27 KB unused (34%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 231 KB
231 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.linuxfoundation.org/_hcms/forms/v2.js200 KB77 KB (40%)✓1st
https://www.googletagmanager.com/gtag/js?id=G-FBYHX832ZD&cx=c&gtm=4e6460157 KB65 KB (41%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-WWBXMJK136 KB62 KB (46%)✓3rd
https://lfx-segment.platform.linuxfoundation.org/latest/lfx-segment-analytics.min.js83 KB27 KB (34%)✓3rd
https://www.linuxfoundation.org/hs/hsstatic/HubspotToolsMenu/static-1.640/js/index.js6 KB—✓1st
https://www.linuxfoundation.org/hubfs/hub_generated/module_assets/1/76935915621/1743138616473/module_Main_Mega_Header.min.js1 KB—✓1st
https://www.linuxfoundation.org/hs/hsstatic/cos-i18n/static-1.53/bundles/project.js1 KB—✓1st
https://www.linuxfoundation.org/hubfs/hub_generated/template_assets/1/80245626652/1774990405782/template_magnific-popup.min.js8 KB—✓1st
https://www.linuxfoundation.org/hubfs/hub_generated/module_assets/1/76935915621/1743138616473/module_Main_Mega_Header.min.js4 KB—✓1st
https://www.linuxfoundation.org/hubfs/hub_generated/module_assets/1/98141763891/1743138714638/module_Linux_Foundation_Members_API.min.js1 KB—✓1st

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

Consider code splitting or tree shaking to reduce unused code.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
Third-Party Impact
37% third-party, 0 ms blocking
PASS
37% third-party, 0 ms blocking
Info::
Third-party code accounts for 37% of page weight (1.1 MiB of 2.9 MiB)
Info::
Third-party blocking time is low (0 ms)
63%
37%
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
5 fonts (215 KB)
PASS
5 fonts (215 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

215 KB total

Render-blocking

0

of 5

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s FCP 985 ms LCP 1.4 shttps://www.linuxfoundation.org/_hcms/googlefonts/Roboto_Slab/300.woff2300.woff2 https://www.linuxfoundation.org/_hcms/googlefonts/Roboto_Slab/300.woff2 — 42.3 KiB — 0 ms — font-display: swaphttps://www.linuxfoundation.org/_hcms/googlefonts/Open_Sans/regular.woff2regular.woff2 https://www.linuxfoundation.org/_hcms/googlefonts/Open_Sans/regular.woff2 — 44.8 KiB — 0 ms — font-display: swaphttps://www.linuxfoundation.org/_hcms/googlefonts/Roboto_Slab/700.woff2700.woff2 https://www.linuxfoundation.org/_hcms/googlefonts/Roboto_Slab/700.woff2 — 43.3 KiB — 0 ms — font-display: swaphttps://www.linuxfoundation.org/_hcms/googlefonts/Open_Sans/700.woff2700.woff2 https://www.linuxfoundation.org/_hcms/googlefonts/Open_Sans/700.woff2 — 43.0 KiB — 0 ms — font-display: swaphttps://www.linuxfoundation.org/_hcms/googlefonts/Roboto_Slab/regular.woff2regular.woff2 https://www.linuxfoundation.org/_hcms/googlefonts/Roboto_Slab/regular.woff2 — 41.6 KiB — 0 ms — font-display: swap
300.woff2 woff2 swap
Size 42 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
regular.woff2 woff2 swap
Size 45 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
700.woff2 woff2 swap
Size 43 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
700.woff2 woff2 swap
Size 43 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
regular.woff2 woff2 swap
Size 42 KB
Load time 0 ms
Start 0 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+
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+
HTTP Caching
max-age=5 (5 seconds)
PASS
max-age=5 (5 seconds)
Info::
Cache-Control header is set
Got: s-maxage=36000, max-age=5
Info::
Effective TTL: 5 seconds (max-age=5)
Info::
CDN TTL: 10 hours (s-maxage=36000)
Info::
Last-Modified header present
Cache-Control

s-maxage=36000, max-age=5

DirectiveValueMeaning
s-maxage36000CDN caches for 10 hours
max-age5Cache for 5 seconds
Effective TTL: 5 seconds
Network Waterfall
126 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
65% of JavaScript execution is third-party
First-party Third-party 877ms · 363KB · €15/mo
Unattributable
Other
Costly
Execution 393ms
Transfer 0 KB
Monthly Cost €7/mo
cmp.osano.com
Other
Costly
Execution 213ms
Transfer 42 KB
Monthly Cost €4/mo
cdnjs
CDN
Optional
Execution 127ms
Transfer 27 KB
Monthly Cost €2/mo
Google Tag Manager
Tag Manager
Optional
Execution 77ms
Transfer 157 KB
Unused 41%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 66ms
Transfer 136 KB
Unused 46%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Unattributable adds 393ms and costs ~€7/month
  • cmp.osano.com adds 213ms and costs ~€4/month

65% 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 393ms 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

cmp.osano.com takes 213ms 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.

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