Performance
· 15 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.
405 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
605 ms
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
0 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.018
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
405 ms
Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.
605 ms
Page Load Progression
375 ms 750 ms 1.1 s 1.5 s 1.9 s 2.2 s 2.6 s 3.0 sBThird-Party Impact47% third-party, 0 ms blockingREVIEW
CImage OptimizationAction12 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
BJS Bundles13 scripts, 86 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-F1JXXVHTDV | 152 KB | 64 KB (42%) | ✓ | 3rd |
| https://alistapart.com/wp-includes/js/jquery/jquery.min.js?ver=3.7.1 | 31 KB | 22 KB (72%) | ✓ | 1st |
| https://alistapart.com/wp-content/themes/ala/js/loadadchecka.js?ver=1.0 | 1 KB | — | ✓ | 1st |
| https://alistapart.com/wp-content/themes/ala/js/prism/prism.js?ver=1.0 | 4 KB | — | ✓ | 1st |
| https://alistapart.com/wp-content/themes/ala/js/skip-link-focus-fix.js?ver=20151215 | 1 KB | — | ✓ | 1st |
| https://alistapart.com/wp-content/themes/ala/js/adchecka.js?ver=1.0 | 0 KB | — | ✓ | 1st |
| https://alistapart.com/wp-content/themes/ala/js/navigation.js?ver=20151215 | 1 KB | — | ✓ | 1st |
| https://alistapart.com/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.1 | 5 KB | — | ✓ | 1st |
| https://stats.wp.com/e-202616.js | 2 KB | — | ✓ | 3rd |
| https://www.google-analytics.com/analytics.js | 21 KB | — | ✓ | 3rd |
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
A+Page Weight Budget410 KB transferred, 33 requestsPASS
A+Text CompressionAll text resources are compressedPASS
A+JS Execution Cost166ms total JS executionPASS
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://alistapart.com/ | 65ms | 2ms | 1ms | 1st |
| Unattributable | 50ms | 1ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-F1JXXVHTDV | 50ms | 40ms | 9ms | 3rd |
A+Font Loading2 fonts (55 KB)PASS
Web fonts
2
55 KB total
Render-blocking
0
of 2
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 HintsNo optimization neededPASS
APage Weight Inventory33 resources · 410 KB · 86 KB savings availablePASS
~86.5 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 33 resources | 410.3 KiB | ||||||
A+HTTP Cachingmax-age=239 (3 minutes)PASS
max-age=239, must-revalidate
| Directive | Value | Meaning |
|---|---|---|
| max-age | 239 | Cache for 3 minutes |
| must-revalidate | — | Must recheck with server after expiry |
Network Waterfall33 requests over 655msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 50ms | 0 KB | — | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 50ms | 152 KB | 42% | $1/mo | Optional |
61% 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