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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
73
GRADE
C
FIX
3
REVIEW
3
PASS
6
INFO
2

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

Mobile Desktop
91
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
90
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.

1.07 s

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

1.69 s

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

60 ms

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

0.028

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

1.31 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.

3.66 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 3 REVIEW 3 FIX
F
Page Weight Budget
Action
2.7 MB transferred, 99 requests
FIX
2.7 MB transferred, 99 requests
Warning::
Page weighs 10.2 MB (2.7 MB transferred)
Warning::
JavaScript is 1.7 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.7 MB
Info::
Fonts are 528 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 528 KB
Info::
CSS is 367 KB — consider purging unused styles
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
Got: 367 KB
Info::
99 HTTP requests
Info::
Estimated 0.58 g CO2 per page load
2.7 MB / 2.4 MB budget
2.7 MB transferred
99 requests
0.58 g CO2 per page load
JavaScript 1.7 MiB 61%
Fonts 528.0 KiB 19%
CSS 367.2 KiB 13%
Images 128.5 KiB 5%
HTML 62.7 KiB 2%
Other 1.0 KiB 0%
Other 961 B 0%
Other 26 B 0%
0 2.4 MB 4.9 MB
Over 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

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

D
Third-Party Impact
Action
95% third-party, 0 ms blocking
FIX
95% third-party, 0 ms blocking
Warning::
Third-party code accounts for 95% of page weight (2.6 MiB of 2.7 MiB)
Info::
Third-party blocking time is low (0 ms)
95%
First-party Third-party
D
JS Bundles
Action
49 scripts, 467 KB unused
FIX
49 scripts, 467 KB unused
Warning::
https://www.gstatic.com/devrel-devsite/prod/vb4124...: 169 KB unused (56%)
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.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-MZW...: 60 KB unused (44%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-18JR...: 60 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 467 KB
467 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/js/devsite_app_custom_elements_module.js302 KB169 KB (56%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-64EQFFKSHW&l=atDataLayer&cx=c&gtm=4e6411h1142 KB61 KB (43%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-NDV7K7V5&l=atDataLayer129 KB60 KB (47%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-MZWCJPP136 KB60 KB (44%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-18JR3Q8PJ8&cx=c&gtm=4e6420h2146 KB60 KB (41%)✓3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/js/devsite_app_module.js58 KB29 KB (49%)✓3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/js/devsite_app_module.js58 KB29 KB (49%)✓3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/js/devsite_devsite_progress_module.js0 KB—✓3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/js/devsite_devsite_snackbar_module.js0 KB—✓3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/js/devsite_devsite_appearance_selector_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
14 images, 0 KB saveable
REVIEW
14 images, 0 KB saveable
Warning::
https://web.dev/static/images/home-blue_720.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web.dev/static/identity/image/hero-identit... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web.dev/static/learn/css/card_480.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web.dev/static/images/ai-feature_480.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web.dev/static/images/inp-icon-only_480.jp... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web.dev/static/learn/html/card_480.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web.dev/static/learn/javascript/card_480.p... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://web.dev/static/images/blog-header_480.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
14 images 127 KB
0 oversized -0 KB
9 legacy format
8 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

C
JS Execution Cost
Action
1071ms total JS execution
REVIEW
1071ms total JS execution
Warning::
https://web.dev/: 302ms CPU time
Info::
Unattributable: 136ms CPU time
Info::
https://www.gstatic.com/devrel-devsite/prod/vb4124...: 130ms CPU time
Info::
https://www.gstatic.com/devrel-devsite/prod/vb4124...: 121ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-18JR...: 117ms CPU time
Warning::
Third-party scripts: 768ms (72% of total)

Main Thread Breakdown

Script Evaluation 45% Other 20% Style & Layout 19% Script Parsing & Compilation 10% Rendering 3%
ScriptTotalScriptingParse/CompileParty
https://web.dev/302ms9ms1ms1st
Unattributable136ms9ms0ms3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/js/devsite_app_module.js130ms69ms6ms3rd
https://www.gstatic.com/devrel-devsite/prod/vb4124e0eb36966d1f5cf3a7ca116e70a424f5334bce4dd1449f7f3a599cf8e09/js/devsite_app_custom_elements_module.js121ms72ms36ms3rd
https://www.googletagmanager.com/gtag/js?id=G-18JR3Q8PJ8&cx=c&gtm=4e6420h2117ms99ms17ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-NDV7K7V5&l=atDataLayer93ms69ms22ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-MZWCJPP91ms75ms14ms3rd
https://www.googletagmanager.com/gtag/js?id=G-64EQFFKSHW&l=atDataLayer&cx=c&gtm=4e6411h181ms67ms13ms3rd
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+
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
12 fonts (528 KB)
PASS
12 fonts (528 KB)
Info::
12 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

12

528 KB total

Render-blocking

0

of 12

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s FCP 1.1 s LCP 1.7 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/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBHMdazQ.woff2 — 36.7 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBA.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBA.woff2 — 42.2 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/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3KUBGEe.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3KUBGEe.woff2 — 28.7 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3iUBGEe.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3iUBGEe.woff2 — 23.1 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMawCUBGEe.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMawCUBGEe.woff2 — 40.4 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3-UBGEe.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3-UBGEe.woff2 — 17.2 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3OUBGEe.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v51/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3OUBGEe.woff2 — 14.0 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v48/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBA.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v48/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBA.woff2 — 39.2 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/roboto/v48/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBA.woff2KFO7CnqEu92Fr1ME7kSn66a... https://fonts.gstatic.com/s/roboto/v48/KFO7CnqEu92Fr1ME7kSn66aGLdTylUAMa3yUBA.woff2 — 0 B — 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
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 37 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 42 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
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 29 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 23 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 40 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 17 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 14 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 39 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
KFO7CnqEu92Fr1ME7kSn66a... woff2 swap
Size 0 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
99 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 768ms · 913KB · €2/mo
Unattributable
Other
Optional
Execution 136ms
Transfer 0 KB
Monthly Cost €0/mo
www.gstatic.com
Other
Optional
Execution 130ms
Transfer 58 KB
Unused 49%
Monthly Cost €0/mo
www.gstatic.com
Other
Optional
Execution 121ms
Transfer 302 KB
Unused 56%
Monthly Cost €0/mo
Google Tag Manager
Tag Manager
Optional
Execution 117ms
Transfer 146 KB
Unused 41%
Monthly Cost €0/mo
Google Tag Manager
Tag Manager
Optional
Execution 93ms
Transfer 129 KB
Unused 47%
Monthly Cost €0/mo
Google Tag Manager
Tag Manager
Optional
Execution 91ms
Transfer 136 KB
Unused 44%
Monthly Cost €0/mo
Google Tag Manager
Tag Manager
Optional
Execution 81ms
Transfer 142 KB
Unused 43%
Monthly Cost €0/mo

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

56% 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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