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Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
87
GRADE
B
FIX
2
REVIEW
4
PASS
9
INFO
2

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

Mobile Desktop
81
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
93
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
92
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
92
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.

2.35 s

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

3.33 s

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

350 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.

2.35 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.

6.99 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
17
9 PASS 4 REVIEW 2 FIX
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 (738.0 KiB of 738.1 KiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
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.

C
Image Optimization
Action
6 images, 0 KB saveable
REVIEW
6 images, 0 KB saveable
Warning::
https://www.postgresql.org/media/img/about/press/e... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.postgresql.org/media/img/PostgreSQL_Ba... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
6 images 295 KB
0 oversized -0 KB
5 legacy format
2 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

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.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

C
JS Execution Cost
Action
1854ms total JS execution
REVIEW
1854ms total JS execution
Warning::
https://www.postgresql.org/: 676ms CPU time
Warning::
Unattributable: 464ms CPU time
Warning::
https://www.googletagmanager.com/gtag/js?id=G-FGJ6...: 368ms CPU time
Info::
https://www.googletagmanager.com/gtm.js?id=GTM-WC9...: 241ms CPU time
Info::
https://www.google-analytics.com/analytics.js: 105ms CPU time
Warning::
Third-party scripts: 1854ms (100% of total)

Main Thread Breakdown

Script Evaluation 37% Style & Layout 28% Other 17% Script Parsing & Compilation 8% Rendering 5% Parse HTML & CSS 3%
ScriptTotalScriptingParse/CompileParty
https://www.postgresql.org/676ms5ms1ms3rd
Unattributable464ms144ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=G-FGJ68XB9NC&cx=c&_slc=1368ms270ms77ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-WC97NKC241ms180ms57ms3rd
https://www.google-analytics.com/analytics.js105ms88ms10ms3rd
B
JS Bundles
5 scripts, 128 KB unused
REVIEW
5 scripts, 128 KB unused
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-WC9...: 65 KB unused (54%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-FGJ6...: 63 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 128 KB
128 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtm.js?id=GTM-WC97NKC120 KB65 KB (54%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-FGJ68XB9NC&cx=c&_slc=1153 KB63 KB (41%)✓3rd
https://www.postgresql.org/media/js/theme.js?54a05eb20 KB—✓3rd
https://www.postgresql.org/media/js/main.js?54a05eb22 KB—✓3rd
https://www.google-analytics.com/analytics.js21 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

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A
Page Weight Budget
738 KB transferred, 24 requests
PASS
738 KB transferred, 24 requests
Info::
Page weighs 1.5 MB (738 KB transferred)
Info::
24 HTTP requests
Info::
Estimated 0.15 g CO2 per page load
738 KB / 2.4 MB budget
738 KB transferred
24 requests
0.15 g CO2 per page load
JavaScript 296.7 KiB 40%
Images 295.2 KiB 40%
Fonts 89.2 KiB 12%
CSS 45.0 KiB 6%
HTML 6.3 KiB 1%
Other 5.2 KiB 1%
Other 467 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+
Font Loading
3 fonts (89 KB)
PASS
3 fonts (89 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

89 KB total

Render-blocking

0

of 3

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s FCP 2.4 s LCP 3.3 shttps://www.postgresql.org/media/webfonts/latin.woff2latin.woff2 https://www.postgresql.org/media/webfonts/latin.woff2 — 38.9 KiB — 21 ms — font-display: swaphttps://www.postgresql.org/media/webfonts/fa-solid-900.woff2fa-solid-900.woff2 https://www.postgresql.org/media/webfonts/fa-solid-900.woff2 — 38.1 KiB — 28 ms — font-display: swaphttps://www.postgresql.org/media/webfonts/fa-regular-400.woff2fa-regular-400.woff2 https://www.postgresql.org/media/webfonts/fa-regular-400.woff2 — 12.2 KiB — 33 ms — font-display: swap
latin.woff2 woff2 swap
Size 39 KB
Load time 21 ms
Start 372 ms
Risk FOUT — text flashes from fallback to web font
fa-solid-900.woff2 woff2 swap
Size 38 KB
Load time 28 ms
Start 374 ms
Risk FOUT — text flashes from fallback to web font
fa-regular-400.woff2 woff2 swap
Size 12 KB
Load time 33 ms
Start 375 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)
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
24 resources · 738 KB · 128 KB savings available
PASS
24 resources · 738 KB · 128 KB savings available
Info::
Within 1MB page-weight target
Got: 738 KB
Info::
~128 KB of savings available
Warning::
23 third-party resources (100% of weight)
24 resources · 738.1 KiB · 23 third-party Within 1MB page-weight target
Image 41% · 300.2 KiB
JavaScript 40% · 296.7 KiB
Font 12% · 89.2 KiB
CSS 6% · 45.0 KiB
Document 1% · 6.3 KiB
Other 0% · 687 B

~127.8 KiB of savings available

Remove unused JavaScript: 127.8 KiB
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
Network Waterfall
24 requests over 856ms
INFO
0 ms 1.0 s 2.0 s 3.0 s FCP 2.4 s LCP 3.3 shttps://postgresql.org// https://postgresql.org/ — 301 — 111 B — 105 ms — h2https://www.postgresql.org/www.postgresql.org/ https://www.postgresql.org/ — 200 — 6.3 KiB — 28 ms — h2https://www.postgresql.org/media/css/fontawesome.css?54a05eb2www.postgresql.org/media/css/fontaw... https://www.postgresql.org/media/css/fontawesome.css?54a05eb2 — 200 — 7.7 KiB — 28 ms — h2https://www.postgresql.org/media/css/bootstrap-4.4.1.min.csswww.postgresql.org/media/css/bootst... https://www.postgresql.org/media/css/bootstrap-4.4.1.min.css — 200 — 23.4 KiB — 43 ms — h2https://www.postgresql.org/dyncss/base.css?54a05eb2www.postgresql.org/dyncss/base.css?... https://www.postgresql.org/dyncss/base.css?54a05eb2 — 200 — 12.3 KiB — 42 ms — h2https://www.postgresql.org/media/js/theme.js?54a05eb2www.postgresql.org/media/js/theme.j... https://www.postgresql.org/media/js/theme.js?54a05eb2 — 200 — 475 B — 57 ms — h2https://www.postgresql.org/media/img/about/press/elephant.pngwww.postgresql.org/media/img/about/... https://www.postgresql.org/media/img/about/press/elephant.png — 200 — 49.4 KiB — 56 ms — h2https://www.postgresql.org/media/img/PostgreSQL_Badge1.svgwww.postgresql.org/media/img/Postgr... https://www.postgresql.org/media/img/PostgreSQL_Badge1.svg — 200 — 6.6 KiB — 57 ms — h2https://www.postgresql.org/media/css/open-sans-woff.csswww.postgresql.org/media/css/open-s... https://www.postgresql.org/media/css/open-sans-woff.css — 200 — 777 B — 20 ms — h2https://www.postgresql.org/media/css/open-sans-woff2.csswww.postgresql.org/media/css/open-s... https://www.postgresql.org/media/css/open-sans-woff2.css — 200 — 871 B — 21 ms — h2https://www.postgresql.org/media/js/main.js?54a05eb2www.postgresql.org/media/js/main.js... https://www.postgresql.org/media/js/main.js?54a05eb2 — 200 — 2.3 KiB — 52 ms — h2data:image/svg+xml;charset=utf8,%3Csvg viewBox='0 0 30 30' xmlns='http://www.w3.org/2000/svg'%3E%3C…www.w3.org/2000/svg'%3E%3C… data:image/svg+xml;charset=utf8,%3Csvg viewBox='0 0 30 30' xmlns='http://www.w3.org/2000/svg'%3E%3C… — 200 — 0 B — 0 ms — datahttps://www.postgresql.org/media/img/misc/banner.jpgwww.postgresql.org/media/img/misc/b... https://www.postgresql.org/media/img/misc/banner.jpg — 200 — 110.9 KiB — 36 ms — h2https://www.postgresql.org/media/img/misc/training.jpgwww.postgresql.org/media/img/misc/t... https://www.postgresql.org/media/img/misc/training.jpg — 200 — 61.7 KiB — 37 ms — h2https://www.postgresql.org/media/img/misc/bugs.jpgwww.postgresql.org/media/img/misc/b... https://www.postgresql.org/media/img/misc/bugs.jpg — 200 — 66.7 KiB — 38 ms — h2https://www.postgresql.org/media/webfonts/latin.woff2www.postgresql.org/media/webfonts/l... https://www.postgresql.org/media/webfonts/latin.woff2 — 200 — 38.9 KiB — 21 ms — h2https://www.postgresql.org/media/webfonts/fa-solid-900.woff2www.postgresql.org/media/webfonts/f... https://www.postgresql.org/media/webfonts/fa-solid-900.woff2 — 200 — 38.1 KiB — 28 ms — h2https://www.postgresql.org/media/webfonts/fa-regular-400.woff2www.postgresql.org/media/webfonts/f... https://www.postgresql.org/media/webfonts/fa-regular-400.woff2 — 200 — 12.2 KiB — 33 ms — h2https://www.googletagmanager.com/gtm.js?id=GTM-WC97NKCwww.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-WC97NKC — 200 — 120.2 KiB — 56 ms — h2https://www.google-analytics.com/analytics.jswww.google-analytics.com/analytics.... https://www.google-analytics.com/analytics.js — 200 — 20.9 KiB — 17 ms — h2https://www.google-analytics.com/j/collect?v=1&_v=j102&a=94797786&t=pageview&_s=1&dl=https%3A%2F%2Fwww.postgresql.org%2F&ul=en-us&dt=PostgreSQL%3A%20The%20world%27s%20most%20advanced%20open%20source%20database&sr=412x823&vp=412x823&_u=YEBAAEABAAAAACAAI~&jid=503508005&gjid=845537092&cid=2032864332.1776797669&tid=UA-1345454-1&_gid=1944136466.1776797669&_r=1&_slc=1&gtm=45He64h1n81WC97NKCza200&gcd=13l3l3l2l1l1&dma_cps=a&dma=1&tag_exp=0~115938465~115938469~117266400~117384406&npa=1&z=598468384www.google-analytics.com/j/collect?... https://www.google-analytics.com/j/collect?v=1&_v=j102&a=94797786&t=pageview&_s=1&dl=https%3A%2F%2Fwww.postgresql.org%2F&ul=en-us&dt=PostgreSQL%3A%20The%20world%27s%20most%20advanced%20open%20source%20database&sr=412x823&vp=412x823&_u=YEBAAEABAAAAACAAI~&jid=503508005&gjid=845537092&cid=2032864332.1776797669&tid=UA-1345454-1&_gid=1944136466.1776797669&_r=1&_slc=1&gtm=45He64h1n81WC97NKCza200&gcd=13l3l3l2l1l1&dma_cps=a&dma=1&tag_exp=0~115938465~115938469~117266400~117384406&npa=1&z=598468384 — 200 — 467 B — 9 ms — h2https://www.postgresql.org/favicon.icowww.postgresql.org/favicon.ico https://www.postgresql.org/favicon.ico — 200 — 5.0 KiB — 20 ms — h2https://www.googletagmanager.com/gtag/js?id=G-FGJ68XB9NC&cx=c&_slc=1www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-FGJ68XB9NC&cx=c&_slc=1 — 200 — 152.9 KiB — 25 ms — h2https://csp-report.postgresql.org/csp-report.postgresql.org/ https://csp-report.postgresql.org/ — 200 — 109 B — 112 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
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 1854ms · 300KB · €20/mo
www.postgresql.org
Other
Costly
Execution 676ms
Transfer 6 KB
Monthly Cost €7/mo
Unattributable
Other
Costly
Execution 464ms
Transfer 0 KB
Monthly Cost €5/mo
Google Tag Manager
Tag Manager
Costly
Execution 368ms
Transfer 153 KB
Unused 41%
Monthly Cost €4/mo
Google Tag Manager
Tag Manager
Costly
Execution 241ms
Transfer 120 KB
Unused 54%
Monthly Cost €3/mo
Google Analytics
Analytics
Optional
Execution 105ms
Transfer 21 KB
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • www.postgresql.org adds 676ms and costs ~€7/month
  • Unattributable adds 464ms and costs ~€5/month
  • Google Tag Manager adds 368ms and costs ~€4/month
  • Google Tag Manager adds 241ms 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

www.postgresql.org takes 676ms 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

Unattributable takes 464ms 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 368ms 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 241ms 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

54% 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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