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Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
96
GRADE
A
FIX
0
REVIEW
1
PASS
14
INFO
2

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

Mobile Desktop
91
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
66
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.
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.

856 ms

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

1.56 s

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.

0.192

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

856 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.

1.56 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
14 PASS 1 REVIEW
C
Image Optimization
Action
8 images, 0 KB saveable
REVIEW
8 images, 0 KB saveable
Warning::
https://f-droid.org/assets/phone-frame_kEDoOnDDPLn... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://f-droid.org/assets/opencollective_button_i... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://f-droid.org/assets/liberapay_donate_button... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://f-droid.org/assets/fdroid-logo-text_S0MUfk... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
8 images 106 KB
0 oversized -0 KB
8 legacy format
4 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

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

A+
Page Weight Budget
164 KB transferred, 16 requests
PASS
164 KB transferred, 16 requests
Info::
Page weighs 347 KB (164 KB transferred)
Info::
16 HTTP requests
Info::
Estimated 0.03 g CO2 per page load
164 KB / 2.4 MB budget
164 KB transferred
16 requests
0.03 g CO2 per page load
Images 105.8 KiB 65%
Fonts 32.1 KiB 20%
CSS 7.4 KiB 5%
JavaScript 6.8 KiB 4%
HTML 5.6 KiB 3%
Other 4.5 KiB 3%
Other 1.7 KiB 1%
0 2.4 MB 4.9 MB
Under budget
A+
Third-Party Impact
No third-party resources
PASS
No third-party resources
Info::
No third-party resources detected
No third-party resources detected — all resources are first-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
285ms total JS execution
PASS
285ms total JS execution
Info::
Unattributable: 185ms CPU time
Info::
https://f-droid.org/: 101ms CPU time
Warning::
Third-party scripts: 185ms (65% of total)

Main Thread Breakdown

Other 56% Style & Layout 28% Script Evaluation 8% Parse HTML & CSS 4% Rendering 4%
ScriptTotalScriptingParse/CompileParty
Unattributable185ms6ms0ms3rd
https://f-droid.org/101ms3ms0ms1st
A+
Font Loading
1 fonts (32 KB)
PASS
1 fonts (32 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

32 KB total

Render-blocking

0

of 1

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s 1.5 s FCP 856 ms LCP 1.6 shttps://f-droid.org/assets/roboto_ln5c7Pv79kCZw8EjInNILddDbwVxQmaVPE0sjunCivU=.ttfroboto_ln5c7Pv79kCZw8Ej... https://f-droid.org/assets/roboto_ln5c7Pv79kCZw8EjInNILddDbwVxQmaVPE0sjunCivU=.ttf — 32.1 KiB — 64 ms — font-display: swap
roboto_ln5c7Pv79kCZw8Ej... ttf swap
Size 32 KB
Load time 64 ms
Start 234 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
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 ~10 KB and ~20 ms

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

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://f-droid.org/assets/banner_YoMGgpdLnM6lO1-eNiEaJsDGclXrmjSlTM-8RGlLcho=.js3 KB—✓1st
https://f-droid.org/assets/donate_JH0mCNwawhPK42f7esD5bhYNybwPzSBMKoUvyTlH-Gw=.js2 KB—✓1st
https://f-droid.org/assets/sidebar-lang_j4kvB8VghKUiWGs4HpqMvN0Ucx0tTmJ_lRfuoUmiaqc=.js3 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
3 hints, 0 missing preconnects
PASS
3 hints, 0 missing preconnects
Info::
Page uses 3 resource hint(s)

Current Resource Hints

preconnect
—
preload
2
dns-prefetch
1
prefetch
—

3 resource hints configured

A+
Page Weight Inventory
16 resources · 164 KB · 0 KB savings available
PASS
16 resources · 164 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 164 KB
16 resources · 163.8 KiB · 0 third-party Within 1MB page-weight target
Image 67% · 110.2 KiB
Font 20% · 32.1 KiB
CSS 5% · 7.4 KiB
JavaScript 4% · 6.8 KiB
Document 3% · 5.6 KiB
Other 1% · 1.7 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
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Hetzner Online GmbH

A+
HTTP Caching
max-age=600 (10 minutes)
PASS
max-age=600 (10 minutes)
Info::
Cache-Control header is set
Got: max-age=600, public, immutable, stale-while-revalidate=300
Info::
Effective TTL: 10 minutes (max-age=600)
Info::
ETag present — enables conditional (304) responses
Info::
Last-Modified header present
Cache-Control

max-age=600, public, immutable, stale-while-revalidate=300

DirectiveValueMeaning
max-age600Cache for 10 minutes
public—Any cache may store this response
immutable—Content will never change
stale-while-revalidate300Serve stale for 5 minutes while fetching fresh
Effective TTL: 600 seconds
Network Waterfall
16 requests over 531ms
INFO
0 ms 500 ms 1.0 s 1.5 s FCP 856 ms LCP 1.6 shttps://f-droid.org// https://f-droid.org/ — 200 — 5.6 KiB — 223 ms — h2https://f-droid.org/assets/roboto_ln5c7Pv79kCZw8EjInNILddDbwVxQmaVPE0sjunCivU=.ttf/assets/roboto_ln5c7Pv79kCZw8EjInNI... https://f-droid.org/assets/roboto_ln5c7Pv79kCZw8EjInNILddDbwVxQmaVPE0sjunCivU=.ttf — 200 — 32.1 KiB — 64 ms — h2https://f-droid.org/css/main.css/css/main.css https://f-droid.org/css/main.css — 200 — 7.4 KiB — 33 ms — h2https://f-droid.org/assets/fdroid-logo-text_S0MUfk_FsnAYL7n2MQye-34IoSNm6QM6xYjDnMqkufo=.svg/assets/fdroid-logo-text_S0MUfk_Fsn... https://f-droid.org/assets/fdroid-logo-text_S0MUfk_FsnAYL7n2MQye-34IoSNm6QM6xYjDnMqkufo=.svg — 200 — 15.8 KiB — 103 ms — h2https://f-droid.org/assets/download-fdroid-qr_rt62kUMmGMIMhgDgUUWjYefCQjazGqLRlAZ7WOgSSlg=.png/assets/download-fdroid-qr_rt62kUMm... https://f-droid.org/assets/download-fdroid-qr_rt62kUMmGMIMhgDgUUWjYefCQjazGqLRlAZ7WOgSSlg=.png — 200 — 665 B — 100 ms — h2https://f-droid.org/assets/phone-frame_kEDoOnDDPLnsqH4lVaEun9wfQgM9ivrhk5OiUWWdKHc=.png/assets/phone-frame_kEDoOnDDPLnsqH4... https://f-droid.org/assets/phone-frame_kEDoOnDDPLnsqH4lVaEun9wfQgM9ivrhk5OiUWWdKHc=.png — 200 — 14.5 KiB — 98 ms — h2https://f-droid.org/assets/opencollective_button_iIGF0Hixdj0EaYR3Sd7FRigTVcl7QPGu6kaoBmXHjZI=.png/assets/opencollective_button_iIGF0... https://f-droid.org/assets/opencollective_button_iIGF0Hixdj0EaYR3Sd7FRigTVcl7QPGu6kaoBmXHjZI=.png — 200 — 11.9 KiB — 100 ms — h2https://f-droid.org/assets/liberapay_donate_button_GHdOOfmFJNeSXjfjnA-98XtIuEfvE6cNJjHgHOhjdv0=.svg/assets/liberapay_donate_button_GHd... https://f-droid.org/assets/liberapay_donate_button_GHdOOfmFJNeSXjfjnA-98XtIuEfvE6cNJjHgHOhjdv0=.svg — 200 — 2.2 KiB — 100 ms — h2https://f-droid.org/assets/banner_YoMGgpdLnM6lO1-eNiEaJsDGclXrmjSlTM-8RGlLcho=.js/assets/banner_YoMGgpdLnM6lO1-eNiEa... https://f-droid.org/assets/banner_YoMGgpdLnM6lO1-eNiEaJsDGclXrmjSlTM-8RGlLcho=.js — 200 — 2.6 KiB — 99 ms — h2https://f-droid.org/assets/donate_JH0mCNwawhPK42f7esD5bhYNybwPzSBMKoUvyTlH-Gw=.js/assets/donate_JH0mCNwawhPK42f7esD5... https://f-droid.org/assets/donate_JH0mCNwawhPK42f7esD5bhYNybwPzSBMKoUvyTlH-Gw=.js — 200 — 1.7 KiB — 99 ms — h2https://f-droid.org/assets/sidebar-lang_j4kvB8VghKUiWGs4HpqMvN0Ucx0tTmJ_lRfuoUmiaqc=.js/assets/sidebar-lang_j4kvB8VghKUiWG... https://f-droid.org/assets/sidebar-lang_j4kvB8VghKUiWGs4HpqMvN0Ucx0tTmJ_lRfuoUmiaqc=.js — 200 — 2.6 KiB — 99 ms — h2https://f-droid.org/assets/mastodon_-c62Zo613I00cO-RavNTybrSJhBC3vZToN5u4zSoMdM=.svg/assets/mastodon_-c62Zo613I00cO-Rav... https://f-droid.org/assets/mastodon_-c62Zo613I00cO-RavNTybrSJhBC3vZToN5u4zSoMdM=.svg — 200 — 2.2 KiB — 99 ms — h2https://f-droid.org/assets/site_J9OLInBmO2hLlutzRFC4mdstNJjL44B6NzBbT0ecmA0=.webmanifest/assets/site_J9OLInBmO2hLlutzRFC4md... https://f-droid.org/assets/site_J9OLInBmO2hLlutzRFC4mdstNJjL44B6NzBbT0ecmA0=.webmanifest — 200 — 1.7 KiB — 96 ms — h2https://f-droid.org/assets/fdroid-screenshot-en.png/assets/fdroid-screenshot-en.png https://f-droid.org/assets/fdroid-screenshot-en.png — 200 — 56.9 KiB — 48 ms — h2https://f-droid.org/assets/ic_search_black_24px.svg/assets/ic_search_black_24px.svg https://f-droid.org/assets/ic_search_black_24px.svg — 200 — 1.6 KiB — 48 ms — h2https://f-droid.org/assets/favicon_yJPr4UNteJc-cseeq16P0Hvl1kDbJjTVYcj-KA6-_Fs=.ico/assets/favicon_yJPr4UNteJc-cseeq16... https://f-droid.org/assets/favicon_yJPr4UNteJc-cseeq16P0Hvl1kDbJjTVYcj-KA6-_Fs=.ico — 200 — 4.5 KiB — 158 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
65% of JavaScript execution is third-party
First-party Third-party 185ms · 0KB · $2/mo
Unattributable
Other
Optional
Execution 185ms
Transfer 0 KB
Monthly Cost $2/mo

65% of JavaScript execution time comes from third-party scripts.

Why this matters

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

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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