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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
83
GRADE
B
FIX
0
REVIEW
5
PASS
7
INFO
2

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

Mobile Desktop
99
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.
96
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.

727 ms

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

733 ms

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

86 ms

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

0.001

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

727 ms

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

1.45 s

Page Load Progression

411 ms
821 ms
1.2 s
1.6 s
2.1 s
2.5 s
2.9 s
3.3 s
Checks
14
7 PASS 5 REVIEW
B
Third-Party Impact
59% third-party, 0 ms blocking
REVIEW
59% third-party, 0 ms blocking
Warning::
Third-party code accounts for 59% of page weight (458.0 KiB of 771.2 KiB)
Info::
Third-party blocking time is low (0 ms)
41%
59%
First-party Third-party
B
Image Optimization
23 images, 0 KB saveable
REVIEW
23 images, 0 KB saveable
Info::
All images are well-optimized
23 images 115 KB
0 oversized -0 KB
22 legacy format
0 missing dimensions CLS risk
B
JS Execution Cost
677ms total JS execution
REVIEW
677ms total JS execution
Info::
Unattributable: 155ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-MQ77...: 127ms CPU time
Info::
https://www.mozilla.org/en-US/: 122ms CPU time
Info::
https://www.mozilla.org/media/js/newsletter.988c40...: 119ms CPU time
Info::
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a4...: 90ms CPU time
Warning::
Third-party scripts: 437ms (64% of total)

Main Thread Breakdown

Script Evaluation 38% Style & Layout 25% Other 23% Script Parsing & Compilation 7%
ScriptTotalScriptingParse/CompileParty
Unattributable155ms6ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=G-MQ7767QQQW&cx=c&gtm=4e6411127ms100ms18ms3rd
https://www.mozilla.org/en-US/122ms4ms0ms1st
https://www.mozilla.org/media/js/newsletter.988c40f6c26c.js119ms2ms0ms1st
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a490-390a1aebf6dd/ui.js90ms72ms13ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-MW3R8V&l=dataLayer65ms48ms14ms3rd
C
JS Bundles
Action
15 scripts, 202 KB unused
REVIEW
15 scripts, 202 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-MQ77...: 70 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-MW3...: 59 KB unused (48%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a4...: 45 KB unused (46%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a4...: 28 KB unused (54%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 202 KB
202 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-MQ7767QQQW&cx=c&gtm=4e6411175 KB70 KB (40%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-MW3R8V&l=dataLayer125 KB59 KB (48%)✓3rd
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a490-390a1aebf6dd/ui.js99 KB45 KB (46%)✓3rd
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a490-390a1aebf6dd/airgap.js52 KB28 KB (54%)✓3rd
https://www.mozilla.org/media/js/fxa.f30434397531.js3 KB—✓1st
https://www.mozilla.org/media/js/lib.c244ff81b28a.js6 KB—✓1st
https://www.mozilla.org/media/js/sentry.31edfa94a7f6.js19 KB—✓1st
https://www.mozilla.org/media/js/data.a85f0425619e.js3 KB—✓1st
https://www.mozilla.org/media/js/m24-ui.71f62c655696.js4 KB—✓1st
https://www.mozilla.org/media/js/stub-attribution.819aeb6b157b.js3 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
Page Weight Budget
771 KB transferred, 53 requests
PASS
771 KB transferred, 53 requests
Info::
Page weighs 2.0 MB (771 KB transferred)
Info::
53 HTTP requests
Info::
Estimated 0.16 g CO2 per page load
771 KB / 2.4 MB budget
771 KB transferred
53 requests
0.16 g CO2 per page load
JavaScript 497.6 KiB 65%
Images 115.3 KiB 15%
Fonts 107.1 KiB 14%
CSS 25.4 KiB 3%
HTML 21.3 KiB 3%
Other 3.0 KiB 0%
Other 1.4 KiB 0%
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+
Font Loading
4 fonts (107 KB)
PASS
4 fonts (107 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

107 KB total

Render-blocking

0

of 4

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 727 ms LCP 733 mshttps://www.mozilla.org/media/protocol/fonts/mozilla-text/MozillaText-SemiBold.b126cc23eddf.woff2MozillaText-SemiBold.b1... https://www.mozilla.org/media/protocol/fonts/mozilla-text/MozillaText-SemiBold.b126cc23eddf.woff2 — 26.2 KiB — 0 ms — font-display: swaphttps://www.mozilla.org/media/protocol/fonts/mozilla-headline/MozillaHeadline-SemiBold.bccc6c46c123.woff2MozillaHeadline-SemiBol... https://www.mozilla.org/media/protocol/fonts/mozilla-headline/MozillaHeadline-SemiBold.bccc6c46c123.woff2 — 28.5 KiB — 0 ms — font-display: swaphttps://www.mozilla.org/media/protocol/fonts/mozilla-text/MozillaText-Regular.71c103450d6d.woff2MozillaText-Regular.71c... https://www.mozilla.org/media/protocol/fonts/mozilla-text/MozillaText-Regular.71c103450d6d.woff2 — 26.2 KiB — 0 ms — font-display: swaphttps://www.mozilla.org/media/protocol/fonts/mozilla-text/MozillaText-Bold.4af7ce689fd6.woff2MozillaText-Bold.4af7ce... https://www.mozilla.org/media/protocol/fonts/mozilla-text/MozillaText-Bold.4af7ce689fd6.woff2 — 26.3 KiB — 0 ms — font-display: swap
MozillaText-SemiBold.b1... woff2 swap
Size 26 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
MozillaHeadline-SemiBol... woff2 swap
Size 28 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
MozillaText-Regular.71c... woff2 swap
Size 26 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
MozillaText-Bold.4af7ce... woff2 swap
Size 26 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=600 (10 minutes)
PASS
max-age=600 (10 minutes)
Info::
Cache-Control header is set
Got: max-age=600
Info::
Effective TTL: 10 minutes (max-age=600)
Info::
ETag present — enables conditional (304) responses
Cache-Control

max-age=600

DirectiveValueMeaning
max-age600Cache for 10 minutes
Effective TTL: 600 seconds
Network Waterfall
53 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
64% of JavaScript execution is third-party
First-party Third-party 437ms · 399KB · €5/mo
Unattributable
Other
Optional
Execution 155ms
Transfer 0 KB
Monthly Cost €2/mo
Google Tag Manager
Tag Manager
Optional
Execution 127ms
Transfer 175 KB
Unused 40%
Monthly Cost €1/mo
transcend-cdn.com
Other
Optional
Execution 90ms
Transfer 99 KB
Unused 46%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 65ms
Transfer 125 KB
Unused 48%
Monthly Cost €1/mo

64% 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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