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Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
76
GRADE
C
FIX
3
REVIEW
2
PASS
9
INFO
2

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

Mobile Desktop
53
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.
92
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.

9.47 s

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

34.38 s

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

206 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.

9.47 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.

35.14 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
16
9 PASS 2 REVIEW 3 FIX
F
Page Weight Budget
Action
12.9 MB transferred, 97 requests
FIX
12.9 MB transferred, 97 requests
Critical::
Page weighs 14.9 MB (12.9 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 2.7 g CO2 per page load
12.9 MB / 2.4 MB budget
12.9 MB transferred
97 requests
2.7 g CO2 per page load
Images 5.4 MiB 42%
Other 5.3 MiB 41%
Fonts 1.4 MiB 11%
JavaScript 829.2 KiB 6%
CSS 29.6 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

F
JS Execution Cost
Action
3598ms total JS execution
FIX
3598ms total JS execution
Warning::
Unattributable: 1143ms CPU time
Warning::
https://flutter.dev/: 1134ms CPU time
Warning::
https://flutter.dev/main.client.dart.js: 443ms CPU time
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-ND4...: 267ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-04YG...: 235ms CPU time
Warning::
Third-party scripts: 2021ms (56% of total)

Main Thread Breakdown

Other 43% Script Evaluation 28% Style & Layout 19% Script Parsing & Compilation 6%
ScriptTotalScriptingParse/CompileParty
Unattributable1143ms44ms0ms3rd
https://flutter.dev/1134ms6ms2ms1st
https://flutter.dev/main.client.dart.js443ms350ms22ms1st
https://www.googletagmanager.com/gtm.js?id=GTM-ND4LWWZ267ms218ms42ms3rd
https://www.googletagmanager.com/gtag/js?id=G-04YGWK0175&cx=c&gtm=4e6460235ms192ms41ms3rd
https://www.gstatic.com/recaptcha/releases/kUYUkUlSyqkjTSMaN2w3RaOh/recaptcha__en.js187ms90ms96ms3rd
https://www.google-analytics.com/analytics.js98ms37ms4ms3rd
https://www.gstatic.com/glue/cookienotificationbar/cookienotificationbar.min.js90ms81ms6ms3rd
D
JS Bundles
Action
29 scripts, 396 KB unused
FIX
29 scripts, 396 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 (39%)
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: 396 KB
396 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 (39%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-ND4LWWZ135 KB57 KB (42%)✓3rd
https://flutter.dev/main.client.dart.js63 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/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/developer-experience.w6... 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/capitalone.229a43d96abb... 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/bmw.7156ff703f63f57817a... 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/ebay.3705d281e7d6d2e4f6... 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/nytimes.74906cb6ccd782a... 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/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/toyota.bf13533e890f3c8a... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://flutter.dev/assets/gpay-developer-story.w3... 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/grab.dc5bf5d55d0c40fd69... 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/emaar.65edd93f0a4a96f72... 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.
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/alibaba.e786e4f856a7898... 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/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/square.9fb506f56f2a61e4... 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
26 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

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
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Third-Party Impact
16% third-party, 0 ms blocking
PASS
16% third-party, 0 ms blocking
Info::
Third-party code accounts for 16% of page weight (2.1 MiB of 12.9 MiB)
Info::
Third-party blocking time is low (0 ms)
84%
16%
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 2.0 s 4.0 s 6.0 s 8.0 s 10.0 s 12.0 s 14.0 s 16.0 s 18.0 s 20.0 s 22.0 s 24.0 s 26.0 s 28.0 s 30.0 s 32.0 s 34.0 s 36.0 s FCP 9.5 s LCP 34.4 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
2 hints, 0 missing preconnects
PASS
2 hints, 0 missing preconnects
Info::
Page uses 2 resource hint(s)

Current Resource Hints

preconnect
2
preload
—
dns-prefetch
—
prefetch
—

2 resource hints configured

A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
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
56% of JavaScript execution is third-party
First-party Third-party 2021ms · 710KB · €22/mo
Unattributable
Other
Costly
Execution 1143ms
Transfer 0 KB
Monthly Cost €12/mo
Google Tag Manager
Tag Manager
Costly
Execution 267ms
Transfer 135 KB
Unused 42%
Monthly Cost €3/mo
Google Tag Manager
Tag Manager
Costly
Execution 235ms
Transfer 164 KB
Unused 39%
Monthly Cost €3/mo
www.gstatic.com
Other
Optional
Execution 187ms
Transfer 362 KB
Unused 68%
Monthly Cost €2/mo
Google Analytics
Analytics
Optional
Execution 98ms
Transfer 21 KB
Monthly Cost €1/mo
www.gstatic.com
Other
Optional
Execution 90ms
Transfer 27 KB
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Unattributable adds 1143ms and costs ~€12/month
  • Google Tag Manager adds 267ms and costs ~€3/month
  • Google Tag Manager adds 235ms and costs ~€3/month

56% 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 1143ms 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 267ms 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 235ms 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

68% of www.gstatic.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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