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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
89
GRADE
B
FIX
1
REVIEW
3
PASS
8
INFO
2

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

Mobile Desktop
65
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
95
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.

3.11 s

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

5.10 s

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

321 ms

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

0.049

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

5.05 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.

5.11 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 3 REVIEW 1 FIX
D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: no-store
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

no-store

DirectiveValueMeaning
no-store—Never cache this response
B
Image Optimization
15 images, 0 KB saveable
REVIEW
15 images, 0 KB saveable
Info::
All images are well-optimized
15 images 94 KB
0 oversized -0 KB
15 legacy format
0 missing dimensions CLS risk
C
JS Execution Cost
Action
1729ms total JS execution
REVIEW
1729ms total JS execution
Warning::
https://developer.mozilla.org/en-US/: 542ms CPU time
Warning::
Unattributable: 502ms CPU time
Warning::
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a4...: 292ms CPU time
Warning::
https://developer.mozilla.org/static/client/1111.5...: 273ms CPU time
Info::
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a4...: 119ms CPU time
Warning::
Third-party scripts: 913ms (53% of total)

Main Thread Breakdown

Script Evaluation 37% Other 31% Style & Layout 21% Rendering 4% Script Parsing & Compilation 4% Parse HTML & CSS 3%
ScriptTotalScriptingParse/CompileParty
https://developer.mozilla.org/en-US/542ms11ms2ms1st
Unattributable502ms36ms0ms3rd
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a490-390a1aebf6dd/ui.js292ms210ms55ms3rd
https://developer.mozilla.org/static/client/1111.53dba753dc3eb961.js273ms242ms0ms1st
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a490-390a1aebf6dd/airgap.js119ms97ms17ms3rd
B
JS Bundles
26 scripts, 74 KB unused
REVIEW
26 scripts, 74 KB unused
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...: 29 KB unused (56%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 74 KB
74 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a490-390a1aebf6dd/ui.js98 KB45 KB (46%)✓3rd
https://transcend-cdn.com/cm/d556c3a1-e57c-4bdf-a490-390a1aebf6dd/airgap.js52 KB29 KB (56%)✓3rd
https://developer.mozilla.org/static/client/3690.b126b99c4de57b27.js1 KB—✓1st
https://developer.mozilla.org/static/client/8280.c6eb5ce3b5879e6f.js2 KB—✓1st
https://developer.mozilla.org/static/client/index.a47e737a9e1899ba.js12 KB—✓1st
https://developer.mozilla.org/static/client/1111.53dba753dc3eb961.js18 KB—✓1st
https://developer.mozilla.org/static/client/6703.145548dea2dbb16d.js1 KB—✓1st
https://developer.mozilla.org/static/client/3611.5ca952c0be37a4a8.js1 KB—✓1st
https://developer.mozilla.org/static/client/2868.b09544148fff25a1.js1 KB—✓1st
https://developer.mozilla.org/static/client/1477.f00a941deda667c8.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

A+
Page Weight Budget
633 KB transferred, 78 requests
PASS
633 KB transferred, 78 requests
Info::
Page weighs 1.2 MB (633 KB transferred)
Info::
Fonts are 246 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 246 KB
Info::
78 HTTP requests
Info::
Estimated 0.13 g CO2 per page load
633 KB / 2.4 MB budget
633 KB transferred
78 requests
0.13 g CO2 per page load
Fonts 245.8 KiB 39%
JavaScript 237.9 KiB 38%
Images 94.3 KiB 15%
CSS 28.3 KiB 4%
HTML 15.3 KiB 2%
Other 5.8 KiB 1%
Other 3.7 KiB 1%
Other 960 B 0%
Other 845 B 0%
0 2.4 MB 4.9 MB
Under budget

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

A
Third-Party Impact
25% third-party, 0 ms blocking
PASS
25% third-party, 0 ms blocking
Info::
Third-party code accounts for 25% of page weight (157.9 KiB of 632.9 KiB)
Info::
Third-party blocking time is low (0 ms)
75%
25%
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
3 fonts (246 KB)
PASS
3 fonts (246 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

246 KB total

Render-blocking

0

of 3

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 FCP 3.1 s LCP 5.1 shttps://developer.mozilla.org/static/client/jetbrains-mono-latin.119994ed445212c7.woff2jetbrains-mono-latin.11... https://developer.mozilla.org/static/client/jetbrains-mono-latin.119994ed445212c7.woff2 — 28.2 KiB — 0 ms — font-display: swaphttps://developer.mozilla.org/static/client/inter-latin.9a3b1bc220d426ef.woff2inter-latin.9a3b1bc220d... https://developer.mozilla.org/static/client/inter-latin.9a3b1bc220d426ef.woff2 — 103.8 KiB — 0 ms — font-display: swaphttps://developer.mozilla.org/static/client/inter-italic-latin.fd2627ec16333c05.woff2inter-italic-latin.fd26... https://developer.mozilla.org/static/client/inter-italic-latin.fd2627ec16333c05.woff2 — 113.8 KiB — 0 ms — font-display: swap
jetbrains-mono-latin.11... woff2 swap
Size 28 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
inter-latin.9a3b1bc220d... woff2 swap
Size 104 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
inter-italic-latin.fd26... woff2 swap
Size 114 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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 ~109 KB and ~218 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
2 hints, 0 missing preconnects
PASS
2 hints, 0 missing preconnects
Info::
Page uses 2 resource hint(s)

Current Resource Hints

preconnect
—
preload
2
dns-prefetch
—
prefetch
—

2 resource hints configured

A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Google Cloud

Network Waterfall
78 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
53% of JavaScript execution is third-party
First-party Third-party 913ms · 151KB · $12/mo
Unattributable
Other
Costly
Execution 502ms
Transfer 0 KB
Monthly Cost $7/mo
transcend-cdn.com
Other
Costly
Execution 292ms
Transfer 98 KB
Unused 46%
Monthly Cost $4/mo
transcend-cdn.com
Other
Optional
Execution 119ms
Transfer 52 KB
Unused 56%
Monthly Cost $2/mo

These scripts may cost more than they're worth

  • Unattributable adds 502ms and costs ~$7/month
  • transcend-cdn.com adds 292ms and costs ~$4/month

53% 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 502ms 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

transcend-cdn.com takes 292ms 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

56% of transcend-cdn.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

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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