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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
70
GRADE
C
FIX
2
REVIEW
3
PASS
7
INFO
2

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

Mobile Desktop
96
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.
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.

779 ms

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

1.13 s

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

63 ms

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

0.001

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

1.18 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.

3.61 s

Page Load Progression

591 ms
1.2 s
1.8 s
2.4 s
3.0 s
3.5 s
4.1 s
4.7 s
Checks
14
7 PASS 3 REVIEW 2 FIX
F
Page Weight Budget
Action
20.8 MB transferred, 117 requests
FIX
20.8 MB transferred, 117 requests
Critical::
Page weighs 26.4 MB (20.8 MB transferred)
Warning::
Images are 18.7 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 18.7 MB
Warning::
JavaScript is 1.2 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.2 MB
Info::
Fonts are 413 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 413 KB
Info::
CSS is 399 KB — consider purging unused styles
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
Got: 399 KB
Warning::
117 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 4.4 g CO2 per page load
20.8 MB / 2.4 MB budget
20.8 MB transferred
117 requests
4.4 g CO2 per page load
Images 18.7 MiB 90%
JavaScript 1.2 MiB 6%
Fonts 413.2 KiB 2%
CSS 399.0 KiB 2%
HTML 101.2 KiB 0%
Other 3.5 KiB 0%
Other 1.2 KiB 0%
Other 551 B 0%
Other 373 B 0%
Other 0 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

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

Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.

Why this matters

CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.

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

F
JS Bundles
Action
55 scripts, 538 KB unused
FIX
55 scripts, 538 KB unused
Warning::
https://www.gstatic.com/devrel-devsite/prod/vb4124...: 156 KB unused (52%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-KFP...: 85 KB unused (55%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-N84...: 62 KB unused (45%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-64EQ...: 61 KB unused (43%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-NDV...: 60 KB unused (47%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 538 KB
538 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/firebase/js/devsite_app_custom_elements_module.js302 KB156 KB (52%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-KFPLMHC154 KB85 KB (55%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-N84485139 KB62 KB (45%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-64EQFFKSHW&l=atDataLayer&cx=c&gtm=4e6411142 KB61 KB (43%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-NDV7K7V5&l=atDataLayer129 KB60 KB (47%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-CW55HF8NVT&cx=c&gtm=4e6420h2147 KB60 KB (40%)✓3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/firebase/js/devsite_app_module.js58 KB27 KB (47%)✓3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/firebase/js/devsite_app_module.js58 KB27 KB (47%)✓3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/firebase/js/devsite_devsite_footer_utility_module.js0 KB—✓3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/firebase/js/devsite_devsite_panel_module.js0 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

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
24 images, 0 KB saveable
REVIEW
24 images, 0 KB saveable
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/products... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/products... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/products... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.gstatic.com/mobilesdk/200629_mobilesdk... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/icons/fi... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/icons/fi... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://firebase.google.com/static/images/integrat... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
24 images 18.7 MB
0 oversized -0 KB
24 legacy format
16 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

C
JS Execution Cost
Action
1700ms total JS execution
REVIEW
1700ms total JS execution
Warning::
Unattributable: 560ms CPU time
Warning::
https://firebase.google.com/: 482ms CPU time
Info::
https://www.googletagmanager.com/gtm.js?id=GTM-N84...: 110ms CPU time
Info::
https://www.gstatic.com/devrel-devsite/prod/vb4124...: 109ms CPU time
Info::
https://www.gstatic.com/devrel-devsite/prod/vb4124...: 106ms CPU time
Warning::
Third-party scripts: 1218ms (72% of total)

Main Thread Breakdown

Script Evaluation 35% Other 34% Style & Layout 17% Script Parsing & Compilation 7%
ScriptTotalScriptingParse/CompileParty
Unattributable560ms50ms0ms3rd
https://firebase.google.com/482ms9ms1ms1st
https://www.googletagmanager.com/gtm.js?id=GTM-N84485110ms85ms15ms3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/firebase/js/devsite_app_custom_elements_module.js109ms55ms40ms3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/firebase/js/devsite_app_module.js106ms77ms7ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-KFPLMHC89ms74ms15ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-NDV7K7V5&l=atDataLayer89ms71ms16ms3rd
https://www.googletagmanager.com/gtag/js?id=G-CW55HF8NVT&cx=c&gtm=4e6420h280ms66ms13ms3rd
https://www.googletagmanager.com/gtag/js?id=G-64EQFFKSHW&l=atDataLayer&cx=c&gtm=4e641175ms62ms12ms3rd
B
HTTP Caching
no-cache, must-revalidate
REVIEW
no-cache, must-revalidate
Info::
Cache-Control header is set
Got: no-cache, must-revalidate
Info::
Last-Modified header present
Cache-Control

no-cache, must-revalidate

DirectiveValueMeaning
no-cache—Cache but always revalidate first
must-revalidate—Must recheck with server after expiry
A+
Third-Party Impact
9% third-party, 0 ms blocking
PASS
9% third-party, 0 ms blocking
Info::
Third-party code accounts for 9% of page weight (1.9 MiB of 20.8 MiB)
Info::
Third-party blocking time is low (0 ms)
91%
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
7 fonts (413 KB)
PASS
7 fonts (413 KB)
Info::
7 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

7

413 KB total

Render-blocking

0

of 7

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 779 ms LCP 1.1 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/materialicons/v145/flUhRq6tzZclQEJ-Vdg-IuiaDsNcIhQ8tQ.woff2flUhRq6tzZclQEJ-Vdg-Iui... https://fonts.gstatic.com/s/materialicons/v145/flUhRq6tzZclQEJ-Vdg-IuiaDsNcIhQ8tQ.woff2 — 125.6 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/jetbrainsmono/v24/tDbV2o-flEEny0FZhsfKu5WU4xD7OwGtT0rU.woff2tDbV2o-flEEny0FZhsfKu5W... https://fonts.gstatic.com/s/jetbrainsmono/v24/tDbV2o-flEEny0FZhsfKu5WU4xD7OwGtT0rU.woff2 — 39.6 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/googlesans/v67/4UasrENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RPjIUvQ.woff24UasrENHsxJlGDuGo1OIlJf... https://fonts.gstatic.com/s/googlesans/v67/4UasrENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RPjIUvQ.woff2 — 35.4 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/materialicons/v145/flUhRq6tzZclQEJ-Vdg-IuiaDsNc.woff2flUhRq6tzZclQEJ-Vdg-Iui... https://fonts.gstatic.com/s/materialicons/v145/flUhRq6tzZclQEJ-Vdg-IuiaDsNc.woff2 — 125.4 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/robotomono/v31/L0x5DF4xlVMF-BfR8bXMIjhLq38.woff2L0x5DF4xlVMF-BfR8bXMIjh... https://fonts.gstatic.com/s/robotomono/v31/L0x5DF4xlVMF-BfR8bXMIjhLq38.woff2 — 32.1 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/googlesans/v67/4UasrENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RPlwUvbQoi-Entw.woff24UasrENHsxJlGDuGo1OIlJf... https://fonts.gstatic.com/s/googlesans/v67/4UasrENHsxJlGDuGo1OIlJfC6l_24rlCK1Yo_Iqcsih3SAyH6cAwhX9RPlwUvbQoi-Entw.woff2 — 19.8 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
flUhRq6tzZclQEJ-Vdg-Iui... woff2 swap
Size 126 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
tDbV2o-flEEny0FZhsfKu5W... woff2 swap
Size 40 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
4UasrENHsxJlGDuGo1OIlJf... woff2 swap
Size 35 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
flUhRq6tzZclQEJ-Vdg-Iui... woff2 swap
Size 125 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
L0x5DF4xlVMF-BfR8bXMIjh... woff2 swap
Size 32 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
4UasrENHsxJlGDuGo1OIlJf... woff2 swap
Size 20 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 ~126 KB and ~252 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+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Google Cloud

Network Waterfall
117 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
72% of JavaScript execution is third-party
First-party Third-party 1218ms · 1072KB · €19/mo
Unattributable
Other
Costly
Execution 560ms
Transfer 0 KB
Monthly Cost €9/mo
Google Tag Manager
Tag Manager
Optional
Execution 110ms
Transfer 139 KB
Unused 45%
Monthly Cost €2/mo
www.gstatic.com
Other
Optional
Execution 109ms
Transfer 302 KB
Unused 52%
Monthly Cost €2/mo
www.gstatic.com
Other
Optional
Execution 106ms
Transfer 58 KB
Unused 47%
Monthly Cost €2/mo
Google Tag Manager
Tag Manager
Optional
Execution 89ms
Transfer 154 KB
Unused 55%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 89ms
Transfer 129 KB
Unused 47%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 80ms
Transfer 147 KB
Unused 40%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 75ms
Transfer 142 KB
Unused 43%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Unattributable adds 560ms and costs ~€9/month

72% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.

Learn more ▾

Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.

Source: web.dev

Unattributable takes 560ms 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

52% 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

55% 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

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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