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https://www.superhuman.com

Performance

· 16 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
77
GRADE
C
FIX
5
REVIEW
1
PASS
8
INFO
2

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

Mobile Desktop
36
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
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.
100
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.

4.06 s

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

16.28 s

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

1.79 s

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.

5.24 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.

18.20 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
8 PASS 1 REVIEW 5 FIX
D
Page Weight Budget
Action
2.5 MB transferred, 78 requests
FIX
2.5 MB transferred, 78 requests
Warning::
Page weighs 5.4 MB (2.5 MB transferred)
Warning::
JavaScript is 1.0 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 1.0 MB
Info::
Fonts are 442 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 442 KB
Info::
78 HTTP requests
Info::
Estimated 0.53 g CO2 per page load
2.5 MB / 2.4 MB budget
2.5 MB transferred
78 requests
0.53 g CO2 per page load
JavaScript 1.0 MiB 41%
Images 821.4 KiB 32%
Fonts 442.1 KiB 17%
HTML 156.6 KiB 6%
Other 58.1 KiB 2%
CSS 38.3 KiB 1%
Other 6.3 KiB 0%
Other 1.5 KiB 0%
Other 1.2 KiB 0%
Other 0 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

D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (2.5 MiB of 2.5 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
F
JS Execution Cost
Action
6453ms total JS execution
FIX
6453ms total JS execution
Warning::
https://superhuman.com/: 1920ms CPU time
Warning::
https://superhumanstatic.com/super-funnel/main/b/0...: 1839ms CPU time
Warning::
Unattributable: 999ms CPU time
Warning::
https://transcend-cdn.com/cm/1c1f8e90-47d0-4bba-a1...: 390ms CPU time
Warning::
https://www.googletagmanager.com/gtag/js?id=G-6MW7...: 292ms CPU time
Warning::
Third-party scripts: 6453ms (100% of total)

Main Thread Breakdown

Script Evaluation 43% Other 28% Style & Layout 10% Rendering 7% Script Parsing & Compilation 5% Garbage Collection 4%
ScriptTotalScriptingParse/CompileParty
https://superhuman.com/1920ms44ms1ms3rd
https://superhumanstatic.com/super-funnel/main/b/0-15521/_next/static/chunks/framework-06defa391493af96.js1839ms1431ms36ms3rd
Unattributable999ms16ms0ms3rd
https://transcend-cdn.com/cm/1c1f8e90-47d0-4bba-a1a2-472d59b002a2/ui.js390ms281ms56ms3rd
https://www.googletagmanager.com/gtag/js?id=G-6MW74FKGFX&cx=c&gtm=4e6460292ms225ms41ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-TNL2F7CJ285ms221ms38ms3rd
https://superhumanstatic.com/super-funnel/main/b/0-15521/_next/static/chunks/pages/render-7def9c6b4f2edef7.js196ms182ms2ms3rd
https://www.googletagmanager.com/gtag/js?id=AW-17616940428&cx=c&gtm=4e6460179ms141ms37ms3rd
https://transcend-cdn.com/cm/1c1f8e90-47d0-4bba-a1a2-472d59b002a2/airgap.js121ms104ms14ms3rd
https://superhumanstatic.com/super-funnel/main/b/0-15521/_next/static/chunks/main-105d281df5ce6448.js95ms77ms18ms3rd

Showing top 10 of 12 scripts

D
JS Bundles
Action
27 scripts, 302 KB unused
FIX
27 scripts, 302 KB unused
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-TNL...: 78 KB unused (52%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-6MW7...: 68 KB unused (38%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=AW-176...: 64 KB unused (45%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://superhumanstatic.com/super-funnel/main/b/0...: 55 KB unused (63%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://transcend-cdn.com/cm/1c1f8e90-47d0-4bba-a1...: 37 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 302 KB
302 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtm.js?id=GTM-TNL2F7CJ151 KB78 KB (52%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-6MW74FKGFX&cx=c&gtm=4e6460177 KB68 KB (38%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-17616940428&cx=c&gtm=4e6460144 KB64 KB (45%)✓3rd
https://superhumanstatic.com/super-funnel/main/b/0-15521/_next/static/chunks/framework-06defa391493af96.js88 KB55 KB (63%)✓3rd
https://transcend-cdn.com/cm/1c1f8e90-47d0-4bba-a1a2-472d59b002a2/ui.js93 KB37 KB (40%)✓3rd
https://superhumanstatic.com/super-funnel/main/b/0-15521/_next/static/chunks/669-8d9692bf6be3aa29.js10 KB—✓3rd
https://superhumanstatic.com/super-funnel/main/b/0-15521/_next/static/chunks/71-66029a225f8fb6fe.js4 KB—✓3rd
https://superhumanstatic.com/super-funnel/main/b/0-15521/_next/static/chunks/516-c6b87318c4dfde27.js6 KB—✓3rd
https://superhumanstatic.com/super-funnel/main/b/0-15521/_next/static/chunks/530.98d153af388991d0.js2 KB—✓3rd
https://superhumanstatic.com/super-funnel/main/b/0-15521/_next/static/chunks/bab35d53-893fddd1ed83b16f.js11 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

F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

B
Image Optimization
17 images, 0 KB saveable
REVIEW
17 images, 0 KB saveable
Info::
All images are well-optimized
17 images 821 KB
0 oversized -0 KB
16 legacy format
0 missing dimensions CLS risk
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
5 fonts (442 KB)
PASS
5 fonts (442 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

442 KB total

Render-blocking

0

of 5

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 FCP 4.1 s LCP 16.3 shttps://superhumanstatic.com/s/fonts/v1/SuperSans-VF-Upright.woff2SuperSans-VF-Upright.woff2 https://superhumanstatic.com/s/fonts/v1/SuperSans-VF-Upright.woff2 — 106.2 KiB — 0 ms — font-display: swaphttps://superhumanstatic.com/s/fonts/v1/SuperSans-VF-Italic.woff2SuperSans-VF-Italic.woff2 https://superhumanstatic.com/s/fonts/v1/SuperSans-VF-Italic.woff2 — 118.2 KiB — 0 ms — font-display: swaphttps://superhumanstatic.com/s/fonts/v1/SuperSerif-VF-Upright.woff2SuperSerif-VF-Upright.w... https://superhumanstatic.com/s/fonts/v1/SuperSerif-VF-Upright.woff2 — 74.0 KiB — 0 ms — font-display: swaphttps://superhumanstatic.com/s/fonts/v1/SuperSerif-VF-Italic.woff2SuperSerif-VF-Italic.woff2 https://superhumanstatic.com/s/fonts/v1/SuperSerif-VF-Italic.woff2 — 81.0 KiB — 0 ms — font-display: swaphttps://superhumanstatic.com/s/fonts/v1/SuperSansMono-VF.woff2SuperSansMono-VF.woff2 https://superhumanstatic.com/s/fonts/v1/SuperSansMono-VF.woff2 — 62.7 KiB — 0 ms — font-display: swap
SuperSans-VF-Upright.woff2 woff2 swap
Size 106 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
SuperSans-VF-Italic.woff2 woff2 swap
Size 118 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
SuperSerif-VF-Upright.w... woff2 swap
Size 74 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
SuperSerif-VF-Italic.woff2 woff2 swap
Size 81 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
SuperSansMono-VF.woff2 woff2 swap
Size 63 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 ~112 KB and ~224 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
15 hints, 0 missing preconnects
PASS
15 hints, 0 missing preconnects
Info::
Page uses 15 resource hint(s)

Current Resource Hints

preconnect
1
preload
+3
13
dns-prefetch
1
prefetch
—

15 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+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall
78 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
100% of JavaScript execution is third-party
First-party Third-party 6453ms · 1087KB · €70/mo
superhuman.com
Other
Costly
Execution 1920ms
Transfer 157 KB
Monthly Cost €21/mo
superhumanstatic.com
Other
Costly
Execution 1839ms
Transfer 88 KB
Unused 63%
Monthly Cost €20/mo
Unattributable
Other
Costly
Execution 999ms
Transfer 0 KB
Monthly Cost €11/mo
transcend-cdn.com
Other
Costly
Execution 390ms
Transfer 93 KB
Unused 40%
Monthly Cost €4/mo
Google Tag Manager
Tag Manager
Costly
Execution 292ms
Transfer 177 KB
Unused 38%
Monthly Cost €3/mo
Google Tag Manager
Tag Manager
Costly
Execution 285ms
Transfer 151 KB
Unused 52%
Monthly Cost €3/mo
superhumanstatic.com
Other
Optional
Execution 196ms
Transfer 2 KB
Monthly Cost €2/mo
Google Tag Manager
Tag Manager
Optional
Execution 179ms
Transfer 144 KB
Unused 45%
Monthly Cost €2/mo
transcend-cdn.com
Other
Optional
Execution 121ms
Transfer 53 KB
Monthly Cost €1/mo
superhumanstatic.com
Other
Optional
Execution 95ms
Transfer 37 KB
Monthly Cost €1/mo
superhumanstatic.com
Other
Optional
Execution 82ms
Transfer 45 KB
Monthly Cost €1/mo
superhumanstatic.com
Other
Optional
Execution 55ms
Transfer 141 KB
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • superhuman.com adds 1920ms and costs ~€21/month
  • superhumanstatic.com adds 1839ms and costs ~€20/month
  • Unattributable adds 999ms and costs ~€11/month
  • transcend-cdn.com adds 390ms and costs ~€4/month
  • Google Tag Manager adds 292ms and costs ~€3/month
  • Google Tag Manager adds 285ms and costs ~€3/month

100% 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

superhuman.com takes 1920ms 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

superhumanstatic.com takes 1839ms 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

63% of superhumanstatic.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

Unattributable takes 999ms 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

transcend-cdn.com takes 390ms 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 292ms 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 285ms 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 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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