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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
86
GRADE
B
FIX
1
REVIEW
5
PASS
6
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.
96
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
92
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.

385 ms

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

745 ms

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

85 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.

656 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.

1.07 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
6 PASS 5 REVIEW 1 FIX
D
JS Execution Cost
Action
2005ms total JS execution
FIX
2005ms total JS execution
Warning::
https://nextjs.org/: 785ms CPU time
Warning::
https://nextjs.org/_next/static/chunks/0jzm94qus19...: 507ms CPU time
Warning::
https://nextjs.org/_next/static/chunks/0q8fapokcqh...: 312ms CPU time
Info::
Unattributable: 232ms CPU time
Info::
https://nextjs.org/_next/static/chunks/40o-_3kv1gk...: 116ms CPU time
Info::
Third-party scripts: 232ms (12% of total)

Main Thread Breakdown

Other 36% Script Evaluation 30% Style & Layout 21% Rendering 8%
ScriptTotalScriptingParse/CompileParty
https://nextjs.org/785ms29ms11ms1st
https://nextjs.org/_next/static/chunks/0jzm94qus19um.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff507ms385ms6ms1st
https://nextjs.org/_next/static/chunks/0q8fapokcqhvs.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff312ms43ms1ms1st
Unattributable232ms8ms0ms3rd
https://nextjs.org/_next/static/chunks/40o-_3kv1gk7b.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff116ms68ms4ms1st
https://nextjs.org/_next/static/chunks/3q8mh8bmyn5n6.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff53ms29ms4ms1st
B
Page Weight Budget
1.3 MB transferred, 122 requests
REVIEW
1.3 MB transferred, 122 requests
Info::
Page weighs 4.5 MB (1.3 MB transferred)
Warning::
JavaScript is 550 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 550 KB
Warning::
122 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.27 g CO2 per page load
1.3 MB / 2.4 MB budget
1.3 MB transferred
122 requests
0.27 g CO2 per page load
JavaScript 549.9 KiB 41%
Images 362.5 KiB 27%
Other 220.9 KiB 17%
CSS 90.4 KiB 7%
Fonts 60.2 KiB 5%
HTML 37.2 KiB 3%
Other 7.9 KiB 1%
Other 351 B 0%
0 2.4 MB 4.9 MB
Under budget

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

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

B
Image Optimization
31 images, 0 KB saveable
REVIEW
31 images, 0 KB saveable
Info::
All images are well-optimized
31 images 363 KB
0 oversized -0 KB
15 legacy format
0 missing dimensions CLS risk
B
JS Bundles
38 scripts, 108 KB unused
REVIEW
38 scripts, 108 KB unused
Warning::
https://nextjs.org/_next/static/chunks/3u5w_3-w5-c...: 34 KB unused (99%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://nextjs.org/_next/static/chunks/40o-_3kv1gk...: 25 KB unused (54%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://nextjs.org/_next/static/chunks/0dliohh_uup...: 25 KB unused (99%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://nextjs.org/_next/static/chunks/0jzm94qus19...: 23 KB unused (33%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 108 KB
108 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://nextjs.org/_next/static/chunks/3u5w_3-w5-c9r.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff36 KB34 KB (99%)✓1st
https://nextjs.org/_next/static/chunks/40o-_3kv1gk7b.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff49 KB25 KB (54%)✓1st
https://nextjs.org/_next/static/chunks/0dliohh_uup9_.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff26 KB25 KB (99%)✓1st
https://nextjs.org/_next/static/chunks/0jzm94qus19um.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff71 KB23 KB (33%)✓1st
https://nextjs.org/_next/static/chunks/02k-gnmv8qw2m.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff16 KB—✓1st
https://nextjs.org/_next/static/chunks/0hf72ym6ap4pb.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff14 KB—✓1st
https://nextjs.org/_next/static/chunks/3czh3m16viwim.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff9 KB—✓1st
https://nextjs.org/_next/static/chunks/3hetyynb8n07-.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff9 KB—✓1st
https://nextjs.org/_next/static/chunks/2xcjob_dpr2i-.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff12 KB—✓1st
https://nextjs.org/_next/static/chunks/3h3oci6el5kdq.js?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff10 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

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
1% third-party, 0 ms blocking
PASS
1% third-party, 0 ms blocking
Info::
Third-party code accounts for 1% of page weight (7.2 KiB of 1.3 MiB)
Info::
Third-party blocking time is low (0 ms)
99%
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
2 fonts (60 KB)
PASS
2 fonts (60 KB)
Info::
2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

2

60 KB total

Render-blocking

0

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 385 ms LCP 745 mshttps://nextjs.org/_next/static/media/797e433ab948586e.p.3f30ggp2vw8zj.woff2?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff797e433ab948586e.p.3f30... https://nextjs.org/_next/static/media/797e433ab948586e.p.3f30ggp2vw8zj.woff2?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff — 30.8 KiB — 0 ms — font-display: swaphttps://nextjs.org/_next/static/media/caa3a2e1cccd8315.p.400zotvijr2rn.woff2?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnffcaa3a2e1cccd8315.p.400z... https://nextjs.org/_next/static/media/caa3a2e1cccd8315.p.400zotvijr2rn.woff2?dpl=dpl_76REKkd1QYthvffCGiAYfiJAQnff — 29.4 KiB — 0 ms — font-display: swap
797e433ab948586e.p.3f30... woff2 swap
Size 31 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
caa3a2e1cccd8315.p.400z... woff2 swap
Size 29 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
Network Waterfall
122 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
12% of JavaScript execution is third-party
First-party Third-party 232ms · 0KB · €3/mo
Unattributable
Other
Costly
Execution 232ms
Transfer 0 KB
Monthly Cost €3/mo

These scripts may cost more than they're worth

  • Unattributable adds 232ms and costs ~€3/month

Unattributable takes 232ms 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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