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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
95
GRADE
A
FIX
0
REVIEW
3
PASS
9
INFO
2

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.
100
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
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.

422 ms

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

709 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.

422 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.

711 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
9 PASS 3 REVIEW
B
Image Optimization
9 images, 0 KB saveable
REVIEW
9 images, 0 KB saveable
Info::
All images are well-optimized
9 images 23 KB
0 oversized -0 KB
6 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

B
HTTP Caching
public,max-age=0,must-revalidate
REVIEW
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

DirectiveValueMeaning
public—Any cache may store this response
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
A+
Page Weight Budget
327 KB transferred, 25 requests
PASS
327 KB transferred, 25 requests
Info::
Page weighs 689 KB (327 KB transferred)
Info::
25 HTTP requests
Info::
Estimated 0.07 g CO2 per page load
327 KB / 2.4 MB budget
327 KB transferred
25 requests
0.07 g CO2 per page load
Fonts 191.4 KiB 59%
HTML 79.6 KiB 24%
Images 23.1 KiB 7%
CSS 19.4 KiB 6%
JavaScript 12.7 KiB 4%
Other 650 B 0%
0 2.4 MB 4.9 MB
Under budget
A+
Third-Party Impact
1% third-party, 0 ms blocking
PASS
1% third-party, 0 ms blocking
Info::
Third-party code accounts for 1% of page weight (3.1 KiB of 326.8 KiB)
Info::
Third-party blocking time is low (0 ms)
99%
First-party Third-party
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
217ms total JS execution
PASS
217ms total JS execution
Info::
https://astro.build/: 157ms CPU time
Info::
Unattributable: 60ms CPU time
Info::
Third-party scripts: 60ms (28% of total)

Main Thread Breakdown

Style & Layout 42% Other 31% Parse HTML & CSS 12% Script Evaluation 9% Rendering 6%
ScriptTotalScriptingParse/CompileParty
https://astro.build/157ms3ms1ms1st
Unattributable60ms6ms0ms3rd
A+
Font Loading
3 fonts (191 KB)
PASS
3 fonts (191 KB)
Info::
3 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

3

191 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 500 ms 1.0 s FCP 422 ms LCP 709 mshttps://astro.build/fonts/Obviously.woff2?v=1Obviously.woff2 https://astro.build/fonts/Obviously.woff2?v=1 — 55.4 KiB — 0 ms — font-display: swaphttps://astro.build/fonts/Inter.woff2?v=1Inter.woff2 https://astro.build/fonts/Inter.woff2?v=1 — 122.3 KiB — 0 ms — font-display: swaphttps://astro.build/fonts/MDIO.woff2?v=1MDIO.woff2 https://astro.build/fonts/MDIO.woff2?v=1 — 13.7 KiB — 0 ms — font-display: swap
Obviously.woff2 woff2 swap
Size 55 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Inter.woff2 woff2 swap
Size 122 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
MDIO.woff2 woff2 swap
Size 14 KB
Load time 0 ms
Start 0 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 ~61 KB and ~122 ms

A+
JS Bundles
9 scripts, 0 KB unused
PASS
9 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://cdn.usefathom.com/script.js3 KB—✓3rd
https://astro.build/_astro/page.QCxfaSnr.js1 KB—✓1st
https://astro.build/_astro/HeaderNav.astro_astro_type_script_index_0_lang.C5vEG38J.js?dpl=69d0e3ffadab8d0008a55f560 KB—✓1st
https://astro.build/_astro/Header.astro_astro_type_script_index_0_lang.3v9wlESP.js?dpl=69d0e3ffadab8d0008a55f561 KB—✓1st
https://astro.build/_astro/CodeBlock.astro_astro_type_script_index_0_lang.elp9ax-4.js?dpl=69d0e3ffadab8d0008a55f561 KB—✓1st
https://astro.build/_astro/ec.0vx5m.js1 KB—✓1st
https://astro.build/.netlify/scripts/rum4 KB—✓1st
https://astro.build/_astro/signals-core.module.CY82nkLF.js?dpl=69d0e3ffadab8d0008a55f562 KB—✓1st
https://astro.build/_astro/dom.Ba-CmOZA.js?dpl=69d0e3ffadab8d0008a55f560 KB—✓1st
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
Network Waterfall
25 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
28% of JavaScript execution is third-party
First-party Third-party 60ms · 0KB · €1/mo
Unattributable
Other
Optional
Execution 60ms
Transfer 0 KB
Monthly Cost €1/mo

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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