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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
76
GRADE
C
FIX
2
REVIEW
3
PASS
7
INFO
2

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

Mobile Desktop
68
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.
91
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.

587 ms

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

5.47 s

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

7 ms

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

0.160

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

1.43 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.

5.58 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
7 PASS 3 REVIEW 2 FIX
F
Page Weight Budget
Action
11.9 MB transferred, 97 requests
FIX
11.9 MB transferred, 97 requests
Critical::
Page weighs 15.2 MB (11.9 MB transferred)
Warning::
Images are 5.4 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 5.4 MB
Info::
Fonts are 1.4 MB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 1.4 MB
Warning::
JavaScript is 829 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 829 KB
Info::
97 HTTP requests
Info::
Estimated 2.5 g CO2 per page load
11.9 MB / 2.4 MB budget
11.9 MB transferred
97 requests
2.5 g CO2 per page load
Images 5.4 MiB 45%
Other 4.3 MiB 36%
Fonts 1.4 MiB 11%
JavaScript 829.5 KiB 7%
CSS 29.5 KiB 0%
HTML 13.6 KiB 0%
Other 1.9 KiB 0%
Other 804 B 0%
Other 449 B 0%
0 2.4 MB 4.9 MB
Over budget

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

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

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

D
JS Bundles
Action
29 scripts, 397 KB unused
FIX
29 scripts, 397 KB unused
Warning::
https://www.gstatic.com/recaptcha/releases/kUYUkUl...: 245 KB unused (68%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-04YG...: 65 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-ND4...: 57 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://flutter.dev/main.client.dart.js: 29 KB unused (46%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 397 KB
397 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.gstatic.com/recaptcha/releases/kUYUkUlSyqkjTSMaN2w3RaOh/recaptcha__en.js362 KB245 KB (68%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-04YGWK0175&cx=c&gtm=4e6460164 KB65 KB (40%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-ND4LWWZ135 KB57 KB (42%)✓3rd
https://flutter.dev/main.client.dart.js64 KB29 KB (46%)✓1st
https://flutter.dev/main.client.dart.js_10.part.js1 KB—✓1st
https://flutter.dev/main.client.dart.js_17.part.js1 KB—✓1st
https://flutter.dev/main.client.dart.js_8.part.js1 KB—✓1st
https://flutter.dev/main.client.dart.js_5.part.js2 KB—✓1st
https://flutter.dev/main.client.dart.js_7.part.js1 KB—✓1st
https://flutter.dev/main.client.dart.js_18.part.js10 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
Image Optimization
Action
50 images, 0 KB saveable
REVIEW
50 images, 0 KB saveable
Warning::
https://flutter.dev/assets/stable-and-reliable.b45... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/capitalone.229a43d96abb... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/mgm.bf7edd6df44c8495b8a... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/nubank.e86e4dc6eb2ae79d... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/seamless-integrations-h... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/alibaba.e786e4f856a7898... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/ebay.3705d281e7d6d2e4f6... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/nytimes.74906cb6ccd782a... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/square.9fb506f56f2a61e4... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/google.f34a21ce43573119... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/flutter-logo.6ed04a8cd7... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/multi-platform.92f0a972... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/sonos.e005df3505351a3dd... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/developer-experience.w6... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/emaar.65edd93f0a4a96f72... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/philips-hue.e5fe6bdbb55... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/bmw.7156ff703f63f57817a... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/abbeyroad.23d27f3c6c7a8... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/dream11.352deaf10e3e303... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/toyota.bf13533e890f3c8a... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/tencent.567ed8d92d9fbc6... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/flutter-logo-white.e475... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/bytedance.d51a1a8d7585d... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/grab.dc5bf5d55d0c40fd69... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/groupon.c667aef71757cca... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
50 images 5.4 MB
0 oversized -0 KB
48 legacy format
25 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

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

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

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

B
JS Execution Cost
806ms total JS execution
REVIEW
806ms total JS execution
Warning::
Unattributable: 301ms CPU time
Warning::
https://flutter.dev/: 275ms CPU time
Info::
https://flutter.dev/main.client.dart.js: 115ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-04YG...: 59ms CPU time
Info::
https://www.googletagmanager.com/gtm.js?id=GTM-ND4...: 56ms CPU time
Warning::
Third-party scripts: 416ms (52% of total)

Main Thread Breakdown

Other 44% Script Evaluation 26% Style & Layout 20% Script Parsing & Compilation 6%
ScriptTotalScriptingParse/CompileParty
Unattributable301ms10ms0ms3rd
https://flutter.dev/275ms2ms0ms1st
https://flutter.dev/main.client.dart.js115ms81ms8ms1st
https://www.googletagmanager.com/gtag/js?id=G-04YGWK0175&cx=c&gtm=4e646059ms49ms10ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-ND4LWWZ56ms47ms9ms3rd
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Third-Party Impact
17% third-party, 0 ms blocking
PASS
17% third-party, 0 ms blocking
Info::
Third-party code accounts for 17% of page weight (2.1 MiB of 11.9 MiB)
Info::
Third-party blocking time is low (0 ms)
83%
17%
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 (1396 KB)
PASS
3 fonts (1396 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

1396 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 587 ms LCP 5.5 shttps://fonts.gstatic.com/s/googlesans/v67/4UasrENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RPjIUvbQoi-E.woff24UasrENHsxJlGDuGo1OIlJf... https://fonts.gstatic.com/s/googlesans/v67/4UasrENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RPjIUvbQoi-E.woff2 — 35.3 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/materialsymbolsrounded/v325/sykO-zNym6YjUruM-QrEh7-nyTnjDwKNJ_190FjpZIvLgyidOK7BDB_Qb9vUe2jjwjHK-P3BukXXkRzDgw.woff2sykO-zNym6YjUruM-QrEh7-... https://fonts.gstatic.com/s/materialsymbolsrounded/v325/sykO-zNym6YjUruM-QrEh7-nyTnjDwKNJ_190FjpZIvLgyidOK7BDB_Qb9vUe2jjwjHK-P3BukXXkRzDgw.woff2 — 1.3 MiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 36.7 KiB — 0 ms — font-display: swap
4UasrENHsxJlGDuGo1OIlJf... woff2 swap
Size 35 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
sykO-zNym6YjUruM-QrEh7-... woff2 swap
Size 1324 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
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 37 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)

Fixing the unchecked items could save ~662 KB and ~1324 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
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A+
HTTP Caching
max-age=3600 (1 hour)
PASS
max-age=3600 (1 hour)
Info::
Cache-Control header is set
Got: max-age=3600
Info::
Effective TTL: 1 hour (max-age=3600)
Info::
ETag present — enables conditional (304) responses
Info::
Last-Modified header present
Cache-Control

max-age=3600

DirectiveValueMeaning
max-age3600Cache for 1 hour
Effective TTL: 3600 seconds
Network Waterfall
97 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
52% of JavaScript execution is third-party
First-party Third-party 416ms · 299KB · €5/mo
Unattributable
Other
Costly
Execution 301ms
Transfer 0 KB
Monthly Cost €3/mo
Google Tag Manager
Tag Manager
Optional
Execution 59ms
Transfer 164 KB
Unused 40%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 56ms
Transfer 135 KB
Unused 42%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Unattributable adds 301ms and costs ~€3/month

52% 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 301ms 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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