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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
83
GRADE
B
FIX
2
REVIEW
2
PASS
8
INFO
2

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

Mobile Desktop
84
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
63
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.
85
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.

1.49 s

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

2.05 s

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

1 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.

1.49 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.

2.05 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
8 PASS 2 REVIEW 2 FIX
F
Page Weight Budget
Action
2.8 MB transferred, 49 requests
FIX
2.8 MB transferred, 49 requests
Warning::
Page weighs 2.8 MB (2.8 MB transferred)
Warning::
Images are 1.3 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.3 MB
Warning::
JavaScript is 900 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 900 KB
Info::
CSS is 426 KB — consider purging unused styles
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
Got: 426 KB
Info::
49 HTTP requests
Info::
Estimated 0.58 g CO2 per page load
2.8 MB / 2.4 MB budget
2.8 MB transferred
49 requests
0.58 g CO2 per page load
Images 1.3 MiB 46%
JavaScript 900.3 KiB 32%
CSS 425.5 KiB 15%
Fonts 181.4 KiB 6%
HTML 12.2 KiB 0%
Other 2.8 KiB 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

Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.

Why this matters

CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.

Source: web.dev

F
JS Bundles
Action
6 scripts, 479 KB unused
FIX
6 scripts, 479 KB unused
Warning::
https://www.eff.org/files/js/js_EvYTiegj0KJZ4sNBg-...: 359 KB unused (55%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.eff.org/files/js/js_EvYTiegj0KJZ4sNBg-...: unminified — 418 KB could be saved
Warning::
https://www.eff.org/files/js/js_qd8BaywA4mj4edyGLb...: 53 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.eff.org/files/js/js_qd8BaywA4mj4edyGLb...: unminified — 28 KB could be saved
Warning::
https://www.eff.org/files/js/js_5qGuLqWqWhHAt7cjYT...: 39 KB unused (74%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.eff.org/files/js/js_x2A4oj9_rCj5CWR_dG...: 28 KB unused (82%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 479 KB
479 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.eff.org/files/js/js_EvYTiegj0KJZ4sNBg-dL-91yeNaZ1KSrlPvKcWK1lr0.js659 KB359 KB (55%)✗1st
https://www.eff.org/files/js/js_qd8BaywA4mj4edyGLb52Px4-BwFqScI7dgPymNmaueA.js134 KB53 KB (40%)✗1st
https://www.eff.org/files/js/js_5qGuLqWqWhHAt7cjYTVS4LFz4Lwl-0kaX6U6Yr0wgkU.js52 KB39 KB (74%)✗1st
https://www.eff.org/files/js/js_x2A4oj9_rCj5CWR_dGMHrobZW14ZVI9ruZKCDG7yyfM.js34 KB28 KB (82%)✓1st
https://www.eff.org/files/js/js_SN-M68YPimsxjKBGXXDOXuxvMRFy2qulwK9OXflHVZo.js20 KB—✗1st
https://www.eff.org/files/js/js_lMrfy51aI91p2ZAdgpEs4r3pZi-E809QDyWJpbMpnTw.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
Image Optimization
Action
33 images, 0 KB saveable
REVIEW
33 images, 0 KB saveable
Warning::
https://www.eff.org/sites/all/modules/custom/eff_l... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.eff.org/files/effectingchange-sitebann... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
33 images 1.3 MB
0 oversized -0 KB
33 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

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

Green Hosting

No green hosting detected

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 (607 B of 2.8 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+
JS Execution Cost
248ms total JS execution
PASS
248ms total JS execution
Info::
Unattributable: 125ms CPU time
Info::
https://www.eff.org/files/js/js_qd8BaywA4mj4edyGLb...: 123ms CPU time
Warning::
Third-party scripts: 125ms (50% of total)

Main Thread Breakdown

Other 41% Style & Layout 28% Script Evaluation 16% Script Parsing & Compilation 7% Parse HTML & CSS 6%
ScriptTotalScriptingParse/CompileParty
Unattributable125ms2ms0ms3rd
https://www.eff.org/files/js/js_qd8BaywA4mj4edyGLb52Px4-BwFqScI7dgPymNmaueA.js123ms37ms5ms1st
A+
Font Loading
5 fonts (181 KB)
PASS
5 fonts (181 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

181 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 2.0 s FCP 1.5 s LCP 2.0 shttps://www.eff.org/sites/all/themes/phoenix/fonts/Montserrat-Regular.woffMontserrat-Regular.woff https://www.eff.org/sites/all/themes/phoenix/fonts/Montserrat-Regular.woff — 17.0 KiB — 0 ms — font-display: swaphttps://www.eff.org/sites/all/themes/phoenix/fonts/Montserrat-Bold.woffMontserrat-Bold.woff https://www.eff.org/sites/all/themes/phoenix/fonts/Montserrat-Bold.woff — 17.1 KiB — 0 ms — font-display: swaphttps://www.eff.org/sites/all/themes/phoenix/fonts/Montserrat-Light.woffMontserrat-Light.woff https://www.eff.org/sites/all/themes/phoenix/fonts/Montserrat-Light.woff — 21.7 KiB — 0 ms — font-display: swaphttps://www.eff.org/sites/all/themes/phoenix/fonts/Merriweather-Regular.woffMerriweather-Regular.woff https://www.eff.org/sites/all/themes/phoenix/fonts/Merriweather-Regular.woff — 62.9 KiB — 0 ms — font-display: swaphttps://www.eff.org/sites/all/themes/phoenix/fonts/Merriweather-Italic.woffMerriweather-Italic.woff https://www.eff.org/sites/all/themes/phoenix/fonts/Merriweather-Italic.woff — 62.7 KiB — 0 ms — font-display: swap
Montserrat-Regular.woff woff swap
Size 17 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
Montserrat-Bold.woff woff swap
Size 17 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
Montserrat-Light.woff woff swap
Size 22 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
Merriweather-Regular.woff woff swap
Size 63 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
Merriweather-Italic.woff woff swap
Size 63 KB
Load time 0 ms
Start 0 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 ~54 KB and ~108 ms

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=1800 (30 minutes)
PASS
max-age=1800 (30 minutes)
Info::
Cache-Control header is set
Got: public, max-age=1800
Info::
Effective TTL: 30 minutes (max-age=1800)
Info::
ETag present — enables conditional (304) responses
Info::
Last-Modified header present
Cache-Control

public, max-age=1800

DirectiveValueMeaning
public—Any cache may store this response
max-age1800Cache for 30 minutes
Effective TTL: 1800 seconds
Network Waterfall
49 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
50% of JavaScript execution is third-party
First-party Third-party 125ms · 0KB · $2/mo
Unattributable
Other
Optional
Execution 125ms
Transfer 0 KB
Monthly Cost $2/mo

50% 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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