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https://paulgraham.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
91
GRADE
A
FIX
1
REVIEW
2
PASS
10
INFO
1

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

Mobile Desktop
100
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
69
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
65
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
75
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.

484 ms

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

723 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.

0.000

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

494 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.

723 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 s
Checks
14
10 PASS 2 REVIEW 1 FIX
D
Third-Party Impact
Action
90% third-party, 0 ms blocking
FIX
90% third-party, 0 ms blocking
Warning::
Third-party code accounts for 90% of page weight (18.4 KiB of 20.5 KiB)
Info::
Third-party blocking time is low (0 ms)
90%
First-party Third-party
B
Image Optimization
6 images, 0 KB saveable
REVIEW
6 images, 0 KB saveable
Info::
All images are well-optimized
6 images 18 KB
0 oversized -0 KB
5 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Page Weight Budget
21 KB transferred, 8 requests
PASS
21 KB transferred, 8 requests
Info::
Page weighs 22 KB (21 KB transferred)
Info::
8 HTTP requests
Info::
Estimated 0.00 g CO2 per page load
21 KB / 2.4 MB budget
21 KB transferred
8 requests
0.00 g CO2 per page load
Images 18.4 KiB 90%
HTML 2.1 KiB 10%
Other 0 B 0%
0 2.4 MB 4.9 MB
Under budget
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+
JS Execution Cost
No JS execution data
PASS
No JS execution data
Info::
No significant JS execution detected

Main Thread Breakdown

Other 63% Style & Layout 21% Script Evaluation 9% Rendering 3%
A+
Font Loading
No web fonts (system fonts)
PASS
No web fonts (system fonts)
Info::
No web fonts loaded — system fonts are fastest
No web fonts loaded — system fonts are optimal.
A+
JS Bundles
No JavaScript
PASS
No JavaScript
Info::
No JavaScript bundles
No JavaScript files loaded.
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
Page Weight Inventory
8 resources · 21 KB · 0 KB savings available
PASS
8 resources · 21 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 21 KB
Warning::
7 third-party resources (90% of weight)
8 resources · 20.5 KiB · 7 third-party Within 1MB page-weight target
Image 90% · 18.4 KiB
Document 10% · 2.1 KiB
Other 0% · 0 B
A
HTTP Caching
max-age=3600 (1 hour)
PASS
max-age=3600 (1 hour)
Info::
Cache-Control header is set
Got: private, max-age=3600
Info::
Effective TTL: 1 hour (max-age=3600)
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

private, max-age=3600

DirectiveValueMeaning
private—Only browser cache, not CDN/proxy
max-age3600Cache for 1 hour
Effective TTL: 3600 seconds
Network Waterfall
8 requests over 668ms
INFO
0 ms 200 ms 400 ms 600 ms FCP 484 ms LCP 723 mshttps://paulgraham.com// https://paulgraham.com/ — 200 — 2.1 KiB — 334 ms — h2https://www.virtumundo.com/images/spacer.gifwww.virtumundo.com/images/spacer.gi... https://www.virtumundo.com/images/spacer.gif — -1 — 0 B — 317 ms — https://s.turbifycdn.com/aah/paulgraham/img-32.gifs.turbifycdn.com/aah/paulgraham/img... https://s.turbifycdn.com/aah/paulgraham/img-32.gif — 200 — 3.6 KiB — 62 ms — h2https://sep.turbifycdn.com/ca/Img/trans_1x1.gifsep.turbifycdn.com/ca/Img/trans_1x1... https://sep.turbifycdn.com/ca/Img/trans_1x1.gif — 200 — 369 B — 63 ms — h2https://s.turbifycdn.com/aah/paulgraham/bel-8.gifs.turbifycdn.com/aah/paulgraham/bel... https://s.turbifycdn.com/aah/paulgraham/bel-8.gif — 200 — 1.8 KiB — 57 ms — h2https://s.turbifycdn.com/aah/paulgraham/index-21.gifs.turbifycdn.com/aah/paulgraham/ind... https://s.turbifycdn.com/aah/paulgraham/index-21.gif — 200 — 11.8 KiB — 58 ms — h2https://s.turbifycdn.com/aah/paulgraham/bel-6.gifs.turbifycdn.com/aah/paulgraham/bel... https://s.turbifycdn.com/aah/paulgraham/bel-6.gif — 200 — 768 B — 49 ms — h2http://ycombinator.com/arc/arc.pngycombinator.com/arc/arc.png http://ycombinator.com/arc/arc.png — -1 — 0 B — 0 ms —
HTML JavaScript CSS Images Fonts XHR/Fetch Other
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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