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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
85
GRADE
B
FIX
0
REVIEW
6
PASS
6
INFO
2

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

Mobile Desktop
100
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.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

354 ms

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

819 ms

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

4 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.

588 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.

1.52 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 6 REVIEW
B
Page Weight Budget
1.1 MB transferred, 68 requests
REVIEW
1.1 MB transferred, 68 requests
Info::
Page weighs 2.5 MB (1.1 MB transferred)
Warning::
JavaScript is 541 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 541 KB
Info::
Fonts are 314 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 314 KB
Info::
68 HTTP requests
Info::
Estimated 0.23 g CO2 per page load
1.1 MB / 2.4 MB budget
1.1 MB transferred
68 requests
0.23 g CO2 per page load
JavaScript 540.8 KiB 49%
Fonts 314.0 KiB 28%
Images 161.0 KiB 15%
HTML 42.8 KiB 4%
Other 21.7 KiB 2%
CSS 20.1 KiB 2%
Other 1.8 KiB 0%
Other 750 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

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

B
Image Optimization
34 images, 0 KB saveable
REVIEW
34 images, 0 KB saveable
Info::
All images are well-optimized
34 images 161 KB
0 oversized -0 KB
31 legacy format
0 missing dimensions CLS risk
B
JS Execution Cost
593ms total JS execution
REVIEW
593ms total JS execution
Info::
https://react.dev/: 181ms CPU time
Info::
https://react.dev/_next/static/chunks/framework-76...: 175ms CPU time
Info::
Unattributable: 105ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-B1E8...: 74ms CPU time
Info::
https://react.dev/_next/static/chunks/811.b2e5ca62...: 58ms CPU time
Info::
Third-party scripts: 180ms (30% of total)

Main Thread Breakdown

Script Evaluation 50% Style & Layout 19% Other 18% Script Parsing & Compilation 8% Parse HTML & CSS 3%
ScriptTotalScriptingParse/CompileParty
https://react.dev/181ms9ms3ms1st
https://react.dev/_next/static/chunks/framework-76ad44d61c11f057.js175ms158ms6ms1st
Unattributable105ms4ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=G-B1E83PJ3RT74ms59ms14ms3rd
https://react.dev/_next/static/chunks/811.b2e5ca620a3f883e.js58ms48ms10ms1st
C
JS Bundles
Action
13 scripts, 174 KB unused
REVIEW
13 scripts, 174 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-B1E8...: 53 KB unused (43%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://react.dev/_next/static/chunks/4ad82c5e.aa0...: 45 KB unused (90%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://react.dev/_next/static/chunks/811.b2e5ca62...: 44 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://react.dev/_next/static/chunks/928-e89de0bd...: 32 KB unused (34%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 174 KB
174 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-B1E83PJ3RT145 KB53 KB (43%)✓3rd
https://react.dev/_next/static/chunks/4ad82c5e.aa059996e264f809.js50 KB45 KB (90%)✓1st
https://react.dev/_next/static/chunks/811.b2e5ca620a3f883e.js110 KB44 KB (40%)✓1st
https://react.dev/_next/static/chunks/928-e89de0bd2e20fa8c.js94 KB32 KB (34%)✓1st
https://react.dev/_next/static/chunks/main-8bc660a98b463b2d.js39 KB—✓1st
https://react.dev/_next/static/chunks/668-9be9de6fa7660277.js34 KB—✓1st
https://react.dev/_next/static/chunks/pages/_app-6d7b64b3b21a9551.js1 KB—✓1st
https://react.dev/_next/static/chunks/pages/%5B%5B...markdownPath%5D%5D-ef91ae665155f68d.js3 KB—✓1st
https://react.dev/_next/static/OjBEcxo-Y95U7B3gD8Cs8/_buildManifest.js1 KB—✓1st
https://react.dev/_next/static/OjBEcxo-Y95U7B3gD8Cs8/_ssgManifest.js0 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::
ETag present — enables conditional (304) responses
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
13% third-party, 0 ms blocking
PASS
13% third-party, 0 ms blocking
Info::
Third-party code accounts for 13% of page weight (145.4 KiB of 1.1 MiB)
Info::
Third-party blocking time is low (0 ms)
87%
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
9 fonts (314 KB)
PASS
9 fonts (314 KB)
Info::
9 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

9

314 KB total

Render-blocking

0

of 9

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 354 ms LCP 819 mshttps://react.dev/fonts/Source-Code-Pro-Regular.woff2Source-Code-Pro-Regular... https://react.dev/fonts/Source-Code-Pro-Regular.woff2 — 74.8 KiB — 0 ms — font-display: swaphttps://react.dev/fonts/Source-Code-Pro-Bold.woff2Source-Code-Pro-Bold.woff2 https://react.dev/fonts/Source-Code-Pro-Bold.woff2 — 75.8 KiB — 0 ms — font-display: swaphttps://react.dev/fonts/Optimistic_Display_W_Md.woff2Optimistic_Display_W_Md... https://react.dev/fonts/Optimistic_Display_W_Md.woff2 — 23.0 KiB — 0 ms — font-display: swaphttps://react.dev/fonts/Optimistic_Display_W_SBd.woff2Optimistic_Display_W_SB... https://react.dev/fonts/Optimistic_Display_W_SBd.woff2 — 23.3 KiB — 0 ms — font-display: swaphttps://react.dev/fonts/Optimistic_Display_W_Bd.woff2Optimistic_Display_W_Bd... https://react.dev/fonts/Optimistic_Display_W_Bd.woff2 — 23.3 KiB — 0 ms — font-display: swaphttps://react.dev/fonts/Optimistic_Text_W_Md.woff2Optimistic_Text_W_Md.woff2 https://react.dev/fonts/Optimistic_Text_W_Md.woff2 — 23.1 KiB — 0 ms — font-display: swaphttps://react.dev/fonts/Optimistic_Text_W_Bd.woff2Optimistic_Text_W_Bd.woff2 https://react.dev/fonts/Optimistic_Text_W_Bd.woff2 — 23.2 KiB — 0 ms — font-display: swaphttps://react.dev/fonts/Optimistic_Text_W_Rg.woff2Optimistic_Text_W_Rg.woff2 https://react.dev/fonts/Optimistic_Text_W_Rg.woff2 — 22.4 KiB — 0 ms — font-display: swaphttps://react.dev/fonts/Optimistic_Text_W_It.woff2Optimistic_Text_W_It.woff2 https://react.dev/fonts/Optimistic_Text_W_It.woff2 — 25.2 KiB — 0 ms — font-display: swap
Source-Code-Pro-Regular... woff2 swap
Size 75 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Source-Code-Pro-Bold.woff2 woff2 swap
Size 76 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Optimistic_Display_W_Md... woff2 swap
Size 23 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Optimistic_Display_W_SB... woff2 swap
Size 23 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Optimistic_Display_W_Bd... woff2 swap
Size 23 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Optimistic_Text_W_Md.woff2 woff2 swap
Size 23 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Optimistic_Text_W_Bd.woff2 woff2 swap
Size 23 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Optimistic_Text_W_Rg.woff2 woff2 swap
Size 22 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Optimistic_Text_W_It.woff2 woff2 swap
Size 25 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
68 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
30% of JavaScript execution is third-party
First-party Third-party 180ms · 145KB · €2/mo
Unattributable
Other
Optional
Execution 105ms
Transfer 0 KB
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 74ms
Transfer 145 KB
Unused 43%
Monthly Cost €1/mo

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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