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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
80
GRADE
B
FIX
1
REVIEW
4
PASS
7
INFO
2

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

Mobile Desktop
61
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
91
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.

1.07 s

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

7.09 s

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

578 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.

2.72 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.

8.70 s

Page Load Progression

470 ms
941 ms
1.4 s
1.9 s
2.4 s
2.8 s
3.3 s
3.8 s
Checks
14
7 PASS 4 REVIEW 1 FIX
F
JS Execution Cost
Action
5007ms total JS execution
FIX
5007ms total JS execution
Warning::
https://jestjs.io/: 2604ms CPU time
Warning::
https://jestjs.io/assets/js/main.17432a57.js: 1242ms CPU time
Warning::
Unattributable: 524ms CPU time
Warning::
https://www.googletagmanager.com/gtag/js?id=UA-443...: 277ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-9V0L...: 214ms CPU time
Info::
Third-party scripts: 1087ms (22% of total)

Main Thread Breakdown

Script Evaluation 33% Other 23% Style & Layout 21% Rendering 17% Script Parsing & Compilation 4%
ScriptTotalScriptingParse/CompileParty
https://jestjs.io/2604ms27ms4ms1st
https://jestjs.io/assets/js/main.17432a57.js1242ms1025ms72ms1st
Unattributable524ms80ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=UA-44373548-17277ms227ms49ms3rd
https://www.googletagmanager.com/gtag/js?id=G-9V0LCYENMT&cx=c&gtm=4e6411214ms154ms58ms3rd
https://jestjs.io/assets/js/8155.4644b154.js74ms59ms15ms1st
https://www.google-analytics.com/analytics.js72ms56ms7ms3rd
C
Page Weight Budget
Action
1.6 MB transferred, 50 requests
REVIEW
1.6 MB transferred, 50 requests
Info::
Page weighs 2.7 MB (1.6 MB transferred)
Warning::
Images are 1.0 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.0 MB
Info::
50 HTTP requests
Info::
Estimated 0.34 g CO2 per page load
1.6 MB / 2.4 MB budget
1.6 MB transferred
50 requests
0.34 g CO2 per page load
Images 1.0 MiB 64%
JavaScript 484.3 KiB 29%
Other 77.7 KiB 5%
CSS 27.7 KiB 2%
HTML 8.5 KiB 1%
Other 566 B 0%
Other 401 B 0%
0 2.4 MB 4.9 MB
Approaching limit

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

C
Image Optimization
Action
22 images, 0 KB saveable
REVIEW
22 images, 0 KB saveable
Warning::
https://jestjs.io/img/logos/nyt.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://jestjs.io/img/logos/airbnb.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://jestjs.io/img/logos/facebook.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://jestjs.io/img/openjs_foundation-logo-horiz... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://jestjs.io/img/logos/twitter.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://jestjs.io/img/logos/spotify.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://jestjs.io/img/logos/instagram.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
22 images 1.0 MB
0 oversized -0 KB
16 legacy format
7 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

C
JS Bundles
Action
21 scripts, 158 KB unused
REVIEW
21 scripts, 158 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-9V0L...: 63 KB unused (43%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=UA-443...: 63 KB unused (51%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://jestjs.io/assets/js/main.17432a57.js: 33 KB unused (23%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 158 KB
158 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-9V0LCYENMT&cx=c&gtm=4e6411144 KB63 KB (43%)✓3rd
https://www.googletagmanager.com/gtag/js?id=UA-44373548-17124 KB63 KB (51%)✓3rd
https://jestjs.io/assets/js/main.17432a57.js140 KB33 KB (23%)✓1st
https://jestjs.io/assets/js/5e95c892.084fbaaf.js0 KB—✓1st
https://jestjs.io/assets/js/a7bd4aaa.b1f047d7.js1 KB—✓1st
https://jestjs.io/assets/js/1646.9c736360.js7 KB—✓1st
https://jestjs.io/assets/js/c4f5d8e4.f64f7276.js6 KB—✓1st
https://jestjs.io/assets/js/a7456010.2a75c070.js0 KB—✓1st
https://jestjs.io/assets/js/3048.004dfdb5.js2 KB—✓1st
https://www.google-analytics.com/analytics.js21 KB—✓3rd

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

B
HTTP Caching
public,max-age=0,must-revalidate
REVIEW
public,max-age=0,must-revalidate
Info::
Cache-Control header is set
Got: public,max-age=0,must-revalidate
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

public,max-age=0,must-revalidate

DirectiveValueMeaning
public—Any cache may store this response
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
A+
Third-Party Impact
19% third-party, 0 ms blocking
PASS
19% third-party, 0 ms blocking
Info::
Third-party code accounts for 19% of page weight (325.1 KiB of 1.6 MiB)
Info::
Third-party blocking time is low (0 ms)
81%
19%
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
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
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
3 hints, 0 missing preconnects
PASS
3 hints, 0 missing preconnects
Info::
Page uses 3 resource hint(s)

Current Resource Hints

preconnect
2
preload
1
dns-prefetch
—
prefetch
—

3 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: Cloudflare

Network Waterfall
50 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
22% of JavaScript execution is third-party
First-party Third-party 1087ms · 289KB · $14/mo
Unattributable
Other
Costly
Execution 524ms
Transfer 0 KB
Monthly Cost $7/mo
Google Tag Manager
Tag Manager
Costly
Execution 277ms
Transfer 124 KB
Unused 51%
Monthly Cost $4/mo
Google Tag Manager
Tag Manager
Costly
Execution 214ms
Transfer 144 KB
Unused 43%
Monthly Cost $3/mo
Google Analytics
Analytics
Optional
Execution 72ms
Transfer 21 KB
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • Unattributable adds 524ms and costs ~$7/month
  • Google Tag Manager adds 277ms and costs ~$4/month
  • Google Tag Manager adds 214ms and costs ~$3/month

Unattributable takes 524ms 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

Google Tag Manager takes 277ms 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

51% of Google Tag Manager'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

Google Tag Manager takes 214ms 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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