Performance
· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
1.94 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
6.36 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
446 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.
5.42 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.
6.38 s
Page Load Progression
DJS Execution CostAction2464ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://bsky.social/about | 698ms | 14ms | 2ms | 1st |
| Unattributable | 606ms | 98ms | 0ms | 3rd |
| https://bsky.social/about/_next/static/chunks/framework-fa877b8be7542607.js | 490ms | 301ms | 34ms | 1st |
| https://www.googletagmanager.com/gtag/js?id=G-WTBZ3K80ET&cx=c>m=4e64k1 | 266ms | 193ms | 72ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-KZT6XPW7 | 180ms | 144ms | 33ms | 3rd |
| https://bsky.social/about/_next/static/chunks/main-2e8f584bd8144e14.js | 100ms | 68ms | 18ms | 1st |
| https://bsky.social/about/_next/static/chunks/pages/_app-e6ca888df01112c8.js | 73ms | 41ms | 15ms | 1st |
| https://bsky.social/about/_next/static/chunks/pages/index-7a2c24e0482c8662.js | 52ms | 45ms | 6ms | 1st |
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction15 images, 0 KB saveableREVIEW
Set explicit width and height to prevent CLS.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
CJS BundlesAction14 scripts, 178 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-WTBZ3K80ET&cx=c>m=4e64k1 | 157 KB | 66 KB (42%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-KZT6XPW7 | 118 KB | 65 KB (55%) | ✓ | 3rd |
| https://bsky.social/about/_next/static/chunks/framework-fa877b8be7542607.js | 59 KB | 28 KB (48%) | ✓ | 1st |
| https://bsky.social/about/_next/static/chunks/pages/_app-e6ca888df01112c8.js | 43 KB | 20 KB (48%) | ✓ | 1st |
| https://bsky.social/about/_next/static/chunks/148-b2a33dd0a80d3cf0.js | 5 KB | — | ✓ | 1st |
| https://bsky.social/about/_next/static/chunks/pages/index-7a2c24e0482c8662.js | 18 KB | — | ✓ | 1st |
| https://bsky.social/about/_next/static/Hgz5X1hWhsfzuSInEWy67/_buildManifest.js | 1 KB | — | ✓ | 1st |
| https://bsky.social/about/_next/static/Hgz5X1hWhsfzuSInEWy67/_ssgManifest.js | 1 KB | — | ✓ | 1st |
| https://bsky.social/about/_next/static/chunks/webpack-705b2d5e34302617.js | 1 KB | — | ✓ | 1st |
| https://bsky.social/about/_next/static/chunks/main-2e8f584bd8144e14.js | 32 KB | — | ✓ | 1st |
Consider code splitting or tree shaking to reduce unused code.
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.
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.
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.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
APage Weight Budget861 KB transferred, 40 requestsPASS
AThird-Party Impact32% third-party, 0 ms blockingPASS
A+Text CompressionAll text resources are compressedPASS
A+Font Loading1 fonts (48 KB)PASS
Web fonts
1
48 KB total
Render-blocking
0
of 1
Dominant font-display
swap
Most common across fonts
Font loading timeline
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)
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource Hints5 hints, 0 missing preconnectsPASS
Current Resource Hints
5 resource hints configured
A+Page Weight Inventory40 resources · 861 KB · 178 KB savings availablePASS
~178.5 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 40 resources | 861.4 KiB | ||||||
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall40 requests over 2664msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 606ms | 0 KB | — | $8/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 266ms | 157 KB | 42% | $4/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 180ms | 118 KB | 55% | $2/mo | Optional |
These scripts may cost more than they're worth
- Unattributable adds 606ms and costs ~$8/month
- Google Tag Manager adds 266ms and costs ~$4/month
43% of JavaScript execution time comes from third-party scripts.
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 606ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
Google Tag Manager takes 266ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
55% of Google Tag Manager's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev