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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
93
GRADE
A
FIX
1
REVIEW
3
PASS
9
INFO
1

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

Mobile Desktop
95
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
59
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.
67
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.

677 ms

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

1.51 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.

0.002

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

911 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.

1.51 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
14
9 PASS 3 REVIEW 1 FIX
D
HTTP Caching
Action
no-store (uncacheable)
FIX
no-store (uncacheable)
Info::
Cache-Control: no-store prevents all caching
Intentional for dynamic content, but increases server load for every page view.
Got: no-cache, no-store
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

no-cache, no-store

DirectiveValueMeaning
no-cache—Cache but always revalidate first
no-store—Never cache this response
B
Page Weight Budget
1.1 MB transferred, 19 requests
REVIEW
1.1 MB transferred, 19 requests
Info::
Page weighs 1.2 MB (1.1 MB transferred)
Info::
19 HTTP requests
Info::
Estimated 0.23 g CO2 per page load
1.1 MB / 2.4 MB budget
1.1 MB transferred
19 requests
0.23 g CO2 per page load
Images 593.6 KiB 52%
JavaScript 348.2 KiB 30%
Fonts 162.3 KiB 14%
CSS 15.4 KiB 1%
Other 15.2 KiB 1%
HTML 6.2 KiB 1%
Other 968 B 0%
Other 710 B 0%
0 2.4 MB 4.9 MB
Under budget
C
Image Optimization
Action
8 images, 0 KB saveable
REVIEW
8 images, 0 KB saveable
Warning::
https://ctan.org/teaser/topic/graphics-3d is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://ctan.org/assets/teaser/M/tex-1-bca293031ef... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
8 images 594 KB
0 oversized -0 KB
8 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 Bundles
Action
3 scripts, 257 KB unused
REVIEW
3 scripts, 257 KB unused
Warning::
https://ctan.org/assets/portal-944f93dcc061b0c8fb3...: 257 KB unused (77%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 257 KB
257 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://ctan.org/assets/portal-944f93dcc061b0c8fb36b9debe744e42.js335 KB257 KB (77%)✓1st
https://ctan.org/assets/lightbox/lightbox.min-7ad53dc7cf622f05176030c7b4352126.js8 KB—✓1st
https://ctan.org/assets/heartbeat-23c92f45463bf81850fbb3e1f20e94b6.js6 KB—✓1st

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

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
No JS execution data
PASS
No JS execution data
Info::
No significant JS execution detected

Main Thread Breakdown

Other 38% Script Evaluation 24% Style & Layout 23% Script Parsing & Compilation 6% Rendering 6% Parse HTML & CSS 3%
A+
Font Loading
1 fonts (162 KB)
PASS
1 fonts (162 KB)
Info::
1 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

1

162 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 677 ms LCP 1.5 shttps://ctan.org/assets/font-awesome-4.7.0/fonts/fontawesome-webfont.ttf?v=4.7.0fontawesome-webfont.ttf https://ctan.org/assets/font-awesome-4.7.0/fonts/fontawesome-webfont.ttf?v=4.7.0 — 162.3 KiB — 102 ms — font-display: swap
fontawesome-webfont.ttf unknown swap
Size 162 KB
Load time 102 ms
Start 357 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
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 ~130 KB and ~260 ms

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
19 resources · 1.1 MB · 257 KB savings available
PASS
19 resources · 1.1 MB · 257 KB savings available
Warning::
Page weight 118 KB over 1MB target
Got: 1.1 MB Expected: ≤ 1 MB
Info::
~257 KB of savings available
Info::
2 resources over 200KB
19 resources · 1.1 MiB · 0 third-party 118.5 KiB over 1MB target
Image 53% · 608.8 KiB
JavaScript 30% · 348.2 KiB
Font 14% · 162.3 KiB
CSS 1% · 15.4 KiB
Document 1% · 6.2 KiB
Other 0% · 1.6 KiB

~256.9 KiB of savings available

Remove unused JavaScript: 256.9 KiB
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: netcup GmbH

Network Waterfall
19 requests over 504ms
INFO
0 ms 500 ms 1.0 s 1.5 s FCP 677 ms LCP 1.5 shttps://ctan.org// https://ctan.org/ — 200 — 6.2 KiB — 113 ms — http/1.1https://ctan.org/assets/portal-944f93dcc061b0c8fb36b9debe744e42.js/assets/portal-944f93dcc061b0c8fb36... https://ctan.org/assets/portal-944f93dcc061b0c8fb36b9debe744e42.js — 200 — 334.5 KiB — 169 ms — http/1.1https://ctan.org/assets/lightbox/lightbox.min-7ad53dc7cf622f05176030c7b4352126.js/assets/lightbox/lightbox.min-7ad53... https://ctan.org/assets/lightbox/lightbox.min-7ad53dc7cf622f05176030c7b4352126.js — 200 — 8.1 KiB — 38 ms — http/1.1https://ctan.org/assets/lightbox/lightbox-a19df1db63f966d9f830ee78a639f137.css/assets/lightbox/lightbox-a19df1db6... https://ctan.org/assets/lightbox/lightbox-a19df1db63f966d9f830ee78a639f137.css — 200 — 1.4 KiB — 74 ms — http/1.1https://ctan.org/assets/heartbeat-23c92f45463bf81850fbb3e1f20e94b6.js/assets/heartbeat-23c92f45463bf8185... https://ctan.org/assets/heartbeat-23c92f45463bf81850fbb3e1f20e94b6.js — 200 — 5.7 KiB — 106 ms — http/1.1https://ctan.org/assets/skin/gray/skin.css/assets/skin/gray/skin.css https://ctan.org/assets/skin/gray/skin.css — 200 — 12.6 KiB — 135 ms — http/1.1https://ctan.org/teaser/topic/graphics-3d/teaser/topic/graphics-3d https://ctan.org/teaser/topic/graphics-3d — 200 — 102.8 KiB — 200 ms — http/1.1https://ctan.org/assets/teaser/M/tex-1-bca293031efb62e5747c5b74f65fff6f.png/assets/teaser/M/tex-1-bca293031efb... https://ctan.org/assets/teaser/M/tex-1-bca293031efb62e5747c5b74f65fff6f.png — 200 — 97.0 KiB — 163 ms — http/1.1https://ctan.org/assets/favicon/manifest-79a60c90526dbf14f7824aa7aa50579f.json/assets/favicon/manifest-79a60c9052... https://ctan.org/assets/favicon/manifest-79a60c90526dbf14f7824aa7aa50579f.json — 200 — 710 B — 104 ms — http/1.1https://ctan.org/assets/skin/print/skin.css/assets/skin/print/skin.css https://ctan.org/assets/skin/print/skin.css — 200 — 1.3 KiB — 37 ms — http/1.1https://ctan.org/assets/skin/gray/images/head-53149a22d92134e6383729796039076c.png/assets/skin/gray/images/head-53149... https://ctan.org/assets/skin/gray/images/head-53149a22d92134e6383729796039076c.png — 200 — 147.5 KiB — 72 ms — http/1.1https://ctan.org/assets/skin/gray/images/ctan-lion-d371c25e7eefcd9e0ada8e810fc88127.svg/assets/skin/gray/images/ctan-lion-... https://ctan.org/assets/skin/gray/images/ctan-lion-d371c25e7eefcd9e0ada8e810fc88127.svg — 200 — 233.4 KiB — 42 ms — http/1.1https://ctan.org/assets/font-awesome-4.7.0/fonts/fontawesome-webfont.ttf?v=4.7.0/assets/font-awesome-4.7.0/fonts/fo... https://ctan.org/assets/font-awesome-4.7.0/fonts/fontawesome-webfont.ttf?v=4.7.0 — 200 — 162.3 KiB — 102 ms — http/1.1https://ctan.org/assets/lightbox/prev.png/assets/lightbox/prev.png https://ctan.org/assets/lightbox/prev.png — 200 — 1.8 KiB — 37 ms — http/1.1https://ctan.org/assets/lightbox/next.png/assets/lightbox/next.png https://ctan.org/assets/lightbox/next.png — 200 — 1.7 KiB — 37 ms — http/1.1https://ctan.org/upload/summary/upload/summary https://ctan.org/upload/summary — 200 — 968 B — 52 ms — http/1.1https://ctan.org/assets/lightbox/loading.gif/assets/lightbox/loading.gif https://ctan.org/assets/lightbox/loading.gif — 200 — 8.7 KiB — 37 ms — http/1.1https://ctan.org/assets/lightbox/close.png/assets/lightbox/close.png https://ctan.org/assets/lightbox/close.png — 200 — 713 B — 37 ms — http/1.1https://ctan.org/assets/favicon/favicon-afd4a866cd0c27587b7b06cd4199a57f.ico/assets/favicon/favicon-afd4a866cd0... https://ctan.org/assets/favicon/favicon-afd4a866cd0c27587b7b06cd4199a57f.ico — 200 — 15.2 KiB — 36 ms — http/1.1
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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