https://a16z.com
Performance
· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.SCORE
79
GRADE
C
FIX
4
REVIEW
2
PASS
9
INFO
2
Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
70
83
100
100
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
3.33 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
4.75 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
34 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.
6.75 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.
4.75 s
Page Load Progression
583 ms 1.2 s 1.7 s 2.3 s
2.9 s
3.5 s
4.1 s
4.7 sChecks
179 PASS 2 REVIEW 4 FIX
FPage Weight BudgetAction12.4 MB transferred, 21 requestsFIX
Page Weight Budget
Action12.4 MB transferred, 21 requests
12.4 MB transferred, 21 requests
Critical::
Page weighs 8.8 MB (12.4 MB transferred)
Info::
21 HTTP requests
Info::
Estimated 2.6 g CO2 per page load
12.4 MB transferred
21 requests
2.6 g CO2 per page load
Other 12.0 MiB 97%
Images 117.3 KiB 1%
JavaScript 103.2 KiB 1%
Fonts 96.7 KiB 1%
CSS 71.5 KiB 1%
HTML 20.1 KiB 0%
Other 857 B 0%
0 2.4 MB 4.9 MB
Over budget
DThird-Party ImpactAction97% third-party, 0 ms blockingFIX
Third-Party Impact
Action97% third-party, 0 ms blocking
97% third-party, 0 ms blocking
Warning::
Third-party code accounts for 97% of page weight (12.0 MiB of 12.4 MiB)
Info::
Third-party blocking time is low (0 ms)
97%
First-party Third-party
DJS Execution CostAction2736ms total JS executionFIX
JS Execution Cost
Action2736ms total JS execution
2736ms total JS execution
Warning::
https://a16z.com/wp-content/themes/a16z/assets/com...: 1189ms CPU time
Warning::
https://a16z.com/: 549ms CPU time
Warning::
Unattributable: 494ms CPU time
Info::
https://a16z.com/wp-content/themes/a16z/assets/com...: 231ms CPU time
Info::
https://a16z.com/wp-content/themes/a16z/assets/com...: 147ms CPU time
Info::
Third-party scripts: 494ms (18% of total)
Main Thread Breakdown
Script Evaluation 39% Other 32% Style & Layout 15% Rendering 10%
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-homepage.js | 1189ms | 753ms | 1ms | 1st |
| https://a16z.com/ | 549ms | 5ms | 4ms | 1st |
| Unattributable | 494ms | 19ms | 0ms | 3rd |
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-core.js | 231ms | 220ms | 1ms | 1st |
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-index.js | 147ms | 41ms | 0ms | 1st |
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-CoreSizes.js | 126ms | 34ms | 0ms | 1st |
DPage Weight InventoryAction21 resources · 12.4 MB · 0 KB savings availableFIX
Page Weight Inventory
Action21 resources · 12.4 MB · 0 KB savings available
21 resources · 12.4 MB · 0 KB savings available
Warning::
Page weight 11.4 MB over 1MB target
Got: 12.4 MB Expected: ≤ 1 MB
Warning::
7 third-party resources (97% of weight)
Info::
1 resources over 200KB
21 resources · 12.4 MiB · 7 third-party 11.4 MiB over 1MB target
Media 97% · 12.0 MiB
Image 1% · 118.2 KiB
JavaScript 1% · 103.2 KiB
Font 1% · 96.7 KiB
CSS 1% · 71.5 KiB
Document 0% · 20.1 KiB
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 21 resources | 12.4 MiB | ||||||
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
ActionWhether the site is served from green-energy infrastructure
Green Hosting
No green hosting detected
BHTTP Cachingpublic,max-age=0,must-revalidateREVIEW
HTTP Caching
public,max-age=0,must-revalidate
public,max-age=0,must-revalidate
Info::
Cache-Control header is set
Got: public,max-age=0,must-revalidate
Info::
ETag present — enables conditional (304) responses
Cache-Control
public,max-age=0,must-revalidate
| Directive | Value | Meaning |
|---|---|---|
| public | — | Any cache may store this response |
| max-age | 0 | Cache for 0 seconds |
| must-revalidate | — | Must recheck with server after expiry |
A+Text CompressionAll text resources are compressedPASS
Text Compression
All text resources are compressed
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+Image Optimization1 images, 0 KB saveablePASS
Image Optimization
1 images, 0 KB saveable
1 images, 0 KB saveable
Info::
All images are well-optimized
1 images 117 KB
0 oversized -0 KB
1 legacy format
0 missing dimensions CLS risk
A+Font Loading3 fonts (97 KB)PASS
Font Loading
3 fonts (97 KB)
3 fonts (97 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
3
97 KB total
Render-blocking
0
of 3
Dominant font-display
swap
Most common across fonts
Font loading timeline
Transfer FOIT (block) FOUT (swap)
vite-DomaineText-Light.... woff2 swap
Size 40 KB
Load time 220 ms
Start 627 ms
Risk FOUT — text flashes from fallback to web font
vite-icomoon.ttf ttf swap
Size 18 KB
Load time 114 ms
Start 628 ms
Risk FOUT — text flashes from fallback to web font
- Convert to woff2 for ~30% smaller file size
vite-DomaineSansText-Li... woff2 swap
Size 39 KB
Load time 130 ms
Start 628 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 ~5 KB and ~10 ms
A+JS Bundles10 scripts, 0 KB unusedPASS
JS Bundles
10 scripts, 0 KB unused
10 scripts, 0 KB unused
0 KB unused JavaScript
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-core.js | 25 KB | — | ✓ | 1st |
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-index.js | 27 KB | — | ✓ | 1st |
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-CoreSizes.js | 1 KB | — | ✓ | 1st |
| https://plausible.io/js/script.manual.js | 2 KB | — | ✓ | 3rd |
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-mainLayout.js | 2 KB | — | ✓ | 1st |
| blob:https://a16z.com/eb4e74c9-80f7-4b6b-89ab-cc20d1c3b092 | -0 KB | — | ✓ | 3rd |
| https://cdn.jsdelivr.net/npm/algoliasearch@4/dist/algoliasearch-lite.umd.js | 5 KB | — | ✓ | 3rd |
| https://a16z.com/wp-includes/js/wp-emoji-release.min.js?ver=6.9.4 | 6 KB | — | ✓ | 1st |
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-Headless.js | 7 KB | — | ✓ | 1st |
| https://a16z.com/wp-content/themes/a16z/assets/compiled/vite/js/vite-homepage.js | 28 KB | — | ✓ | 1st |
A+Resource CachingAll resources properly cachedPASS
Resource Caching
All resources properly cached
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+Critical Rendering PathNo render-blocking resourcesPASS
Critical Rendering Path
No render-blocking resources
No render-blocking resources
Info::
No render-blocking resources detected
A+Resource Hints1 hints, 0 missing preconnectsPASS
Resource Hints
1 hints, 0 missing preconnects
1 hints, 0 missing preconnects
Info::
Page uses 1 resource hint(s)
Current Resource Hints
preconnect—
preload—
dns-prefetch 1
prefetch—
1 resource hints configured
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
Render-Blocking Resources
No render-blocking resources detected
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+Third-Party ResourcesNo third-party resources detectedPASS
Third-Party Resources
No third-party resources detected
No third-party resources detected
Network Waterfall21 requests over 1176msINFO
Network Waterfall
21 requests over 1176ms
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
18% of JavaScript execution is third-party
First-party Third-party 494ms · 0KB · €5/mo
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 494ms | 0 KB | — | €5/mo | Costly |
Unattributable
Other
Execution 494ms
Transfer 0 KB
Monthly Cost €5/mo
These scripts may cost more than they're worth
- Unattributable adds 494ms and costs ~€5/month
Unattributable takes 494ms 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
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.