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https://stelgano.com

Performance

· 21 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
87
GRADE
B
FIX
1
REVIEW
4
PASS
14
INFO
2

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

Mobile Desktop
78
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
95
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.

708 ms

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

4.13 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.

0.008

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

718 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.

4.21 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
21
14 PASS 4 REVIEW 1 FIX
F
Page Weight Budget
Action
5.0 MB transferred, 25 requests
FIX
5.0 MB transferred, 25 requests
Critical::
Page weighs 5.1 MB (5.0 MB transferred)
Warning::
Images are 4.8 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 4.8 MB
Info::
25 HTTP requests
Info::
Estimated 1.0 g CO2 per page load
5.0 MB / 2.4 MB budget
5.0 MB transferred
25 requests
1.0 g CO2 per page load
Images 4.8 MiB 95%
Fonts 193.4 KiB 4%
CSS 15.5 KiB 0%
HTML 13.1 KiB 0%
Other 11.3 KiB 0%
Other 983 B 0%
0 2.4 MB 4.9 MB
Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

C
Image Optimization
Action
9 images, 0 KB saveable
REVIEW
9 images, 0 KB saveable
Warning::
https://stelgano.com/images/contact_steg.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://stelgano.com/images/ephemeral_identity.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://stelgano.com/images/client_side_crypto.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://stelgano.com/images/comparison_visual.jpg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://stelgano.com/images/n_equals_1.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://stelgano.com/images/hero_illustration.png is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://stelgano.com/images/hero_visual.jpg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://stelgano.com/images/zero_knowledge_server.... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
9 images 4.8 MB
0 oversized -0 KB
8 legacy format
8 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

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

B
Server-Timing Observability
No Server-Timing header found
REVIEW
No Server-Timing header found
Info::
No Server-Timing header found
Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.
C
Page Weight Inventory
Action
25 resources · 5.0 MB · 0 KB savings available
REVIEW
25 resources · 5.0 MB · 0 KB savings available
Warning::
Page weight 5.0 MB exceeds 1 MB target by 4.0 MB
Got: 5.0 MB Expected: ≤ 1 MB
Info::
1 third-party resources (0% of weight)
Info::
8 resources over 200KB
25 resources · 5.0 MiB · 1 third-party 4.0 MiB over 1MB target
Image 96% · 4.8 MiB
Font 4% · 193.4 KiB
CSS 0% · 15.5 KiB
Document 0% · 13.1 KiB
Other 0% · 1.5 KiB
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::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
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+
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
499ms total JS execution
PASS
499ms total JS execution
Warning::
Unattributable: 252ms CPU time
Info::
https://stelgano.com/: 248ms CPU time

Main Thread Breakdown

Other 75% Style & Layout 20%
ScriptTotalScriptingParse/CompileParty
Unattributable252ms1ms0ms1st
https://stelgano.com/248ms3ms1ms1st
A+
Font Loading
10 fonts (193 KB)
PASS
10 fonts (193 KB)
Info::
10 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

10

193 KB total

Render-blocking

0

of 10

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 4.0 s FCP 708 ms LCP 4.1 shttps://stelgano.com/fonts/outfit-latin-400-normal.woff2outfit-latin-400-normal... https://stelgano.com/fonts/outfit-latin-400-normal.woff2 — 14.8 KiB — 97 ms — font-display: swaphttps://stelgano.com/fonts/outfit-latin-800-normal.woff2outfit-latin-800-normal... https://stelgano.com/fonts/outfit-latin-800-normal.woff2 — 14.8 KiB — 112 ms — font-display: swaphttps://stelgano.com/fonts/inter-latin-600-normal.woff2inter-latin-600-normal.... https://stelgano.com/fonts/inter-latin-600-normal.woff2 — 25.0 KiB — 113 ms — font-display: swaphttps://stelgano.com/fonts/outfit-latin-700-normal.woff2outfit-latin-700-normal... https://stelgano.com/fonts/outfit-latin-700-normal.woff2 — 15.5 KiB — 119 ms — font-display: swaphttps://stelgano.com/fonts/outfit-latin-300-normal.woff2outfit-latin-300-normal... https://stelgano.com/fonts/outfit-latin-300-normal.woff2 — 14.7 KiB — 117 ms — font-display: swaphttps://stelgano.com/fonts/jetbrains-mono-latin-400-normal.woff2jetbrains-mono-latin-40... https://stelgano.com/fonts/jetbrains-mono-latin-400-normal.woff2 — 21.8 KiB — 111 ms — font-display: swaphttps://stelgano.com/fonts/inter-latin-500-normal.woff2inter-latin-500-normal.... https://stelgano.com/fonts/inter-latin-500-normal.woff2 — 25.4 KiB — 120 ms — font-display: swaphttps://stelgano.com/fonts/inter-latin-400-normal.woff2inter-latin-400-normal.... https://stelgano.com/fonts/inter-latin-400-normal.woff2 — 24.2 KiB — 118 ms — font-display: swaphttps://stelgano.com/fonts/outfit-latin-600-normal.woff2outfit-latin-600-normal... https://stelgano.com/fonts/outfit-latin-600-normal.woff2 — 14.9 KiB — 117 ms — font-display: swaphttps://stelgano.com/fonts/jetbrains-mono-latin-500-normal.woff2jetbrains-mono-latin-50... https://stelgano.com/fonts/jetbrains-mono-latin-500-normal.woff2 — 22.4 KiB — 110 ms — font-display: swap
outfit-latin-400-normal... woff2 swap
Size 15 KB
Load time 97 ms
Start 223 ms
Risk FOUT — text flashes from fallback to web font
outfit-latin-800-normal... woff2 swap
Size 15 KB
Load time 112 ms
Start 224 ms
Risk FOUT — text flashes from fallback to web font
inter-latin-600-normal.... woff2 swap
Size 25 KB
Load time 113 ms
Start 224 ms
Risk FOUT — text flashes from fallback to web font
outfit-latin-700-normal... woff2 swap
Size 15 KB
Load time 119 ms
Start 224 ms
Risk FOUT — text flashes from fallback to web font
outfit-latin-300-normal... woff2 swap
Size 15 KB
Load time 117 ms
Start 225 ms
Risk FOUT — text flashes from fallback to web font
jetbrains-mono-latin-40... woff2 swap
Size 22 KB
Load time 111 ms
Start 225 ms
Risk FOUT — text flashes from fallback to web font
inter-latin-500-normal.... woff2 swap
Size 25 KB
Load time 120 ms
Start 225 ms
Risk FOUT — text flashes from fallback to web font
inter-latin-400-normal.... woff2 swap
Size 24 KB
Load time 118 ms
Start 225 ms
Risk FOUT — text flashes from fallback to web font
outfit-latin-600-normal... woff2 swap
Size 15 KB
Load time 117 ms
Start 226 ms
Risk FOUT — text flashes from fallback to web font
jetbrains-mono-latin-50... woff2 swap
Size 22 KB
Load time 110 ms
Start 226 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+
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+
HTTP/3 (QUIC)
HTTP/3 advertised via Alt-Svc
PASS
HTTP/3 advertised via Alt-Svc
Info::
HTTP/3 (QUIC) is supported
First-load mobile users on cellular networks see meaningful latency improvements with HTTP/3. The QUIC transport collapses TLS + TCP handshakes into one and recovers faster from packet loss.
A+
Compression Algorithm
Main response uses brotli
PASS
Main response uses brotli
Info::
Main HTML response uses brotli (Content-Encoding: br)
Brotli is the best text-compression algorithm for general use, ~20% smaller than gzip on average (40% on smaller files). Modern browsers all support it.
A+
LCP Image Preload
LCP preload audit not available
PASS
LCP preload audit not available
Info::
LCP image preload audit not available for this scan
A+
Main HTML Cache-Control
Main HTML max-age=0 (≤ 5min) is appropriate
PASS
Main HTML max-age=0 (≤ 5min) is appropriate
Info::
Main HTML max-age=0 (≤ 5min) is appropriate
Got: public, max-age=0, must-revalidate
A
Server Response Intelligence
2 server-response signal(s) detected
PASS
2 server-response signal(s) detected
Warning::
Compressed response missing `Vary` header
The page is served with `Content-Encoding: br` but has no `Vary` header. Without `Vary: Accept-Encoding`, intermediary caches (corporate proxies, ISP caches) may serve the compressed variant to clients that didn't send the matching `Accept-Encoding` -- the client sees garbled bytes. Add `Vary: Accept-Encoding` whenever the response is conditionally compressed.
Info::
No `ETag` or `Last-Modified` -- conditional GET not supported
Without either header, browsers can't issue conditional GETs and refresh always re-downloads the full response body even when nothing changed. Add `ETag: "<hash>"` (or `Last-Modified: <date>`) on cacheable responses; the server returns 304 Not Modified when the client's cached copy is still valid, saving bandwidth.
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall
25 requests over 510ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s FCP 708 ms LCP 4.1 shttps://stelgano.com// https://stelgano.com/ — 200 — 13.1 KiB — 70 ms — h3https://stelgano.com/cdn-cgi/speculation/cdn-cgi/speculation https://stelgano.com/cdn-cgi/speculation — 200 — 582 B — 19 ms — h3https://stelgano.com/assets/app.css/assets/app.css https://stelgano.com/assets/app.css — 200 — 15.5 KiB — 52 ms — h3https://stelgano.com/images/hero_visual.jpg/images/hero_visual.jpg https://stelgano.com/images/hero_visual.jpg — 200 — 236.4 KiB — 183 ms — h3https://stelgano.com/images/zero_knowledge_server.png/images/zero_knowledge_server.png https://stelgano.com/images/zero_knowledge_server.png — 200 — 905.8 KiB — 287 ms — h3https://stelgano.com/api/funnel/api/funnel https://stelgano.com/api/funnel — 204 — 983 B — 31 ms — h3https://stelgano.com/images/ephemeral_identity.png/images/ephemeral_identity.png https://stelgano.com/images/ephemeral_identity.png — 200 — 732.0 KiB — 228 ms — h3https://stelgano.com/images/client_side_crypto.png/images/client_side_crypto.png https://stelgano.com/images/client_side_crypto.png — 200 — 722.1 KiB — 229 ms — h3https://stelgano.com/images/comparison_visual.jpg/images/comparison_visual.jpg https://stelgano.com/images/comparison_visual.jpg — 200 — 296.6 KiB — 139 ms — h3https://stelgano.com/images/contact_steg.png/images/contact_steg.png https://stelgano.com/images/contact_steg.png — 200 — 408.4 KiB — 216 ms — h3https://stelgano.com/images/n_equals_1.png/images/n_equals_1.png https://stelgano.com/images/n_equals_1.png — 200 — 751.0 KiB — 231 ms — h3https://stelgano.com/images/hero_illustration.png/images/hero_illustration.png https://stelgano.com/images/hero_illustration.png — 200 — 835.1 KiB — 232 ms — h3https://stelgano.com/icons.svg/icons.svg https://stelgano.com/icons.svg — 200 — 6.5 KiB — 51 ms — h3data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='…www.w3.org/2000/svg'%3E%3Cfilter id... data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='… — 200 — 0 B — 0 ms — datahttps://stelgano.com/fonts/outfit-latin-400-normal.woff2/fonts/outfit-latin-400-normal.woff... https://stelgano.com/fonts/outfit-latin-400-normal.woff2 — 200 — 14.8 KiB — 97 ms — h3https://stelgano.com/fonts/outfit-latin-800-normal.woff2/fonts/outfit-latin-800-normal.woff... https://stelgano.com/fonts/outfit-latin-800-normal.woff2 — 200 — 14.8 KiB — 112 ms — h3https://stelgano.com/fonts/inter-latin-600-normal.woff2/fonts/inter-latin-600-normal.woff2 https://stelgano.com/fonts/inter-latin-600-normal.woff2 — 200 — 25.0 KiB — 113 ms — h3https://stelgano.com/fonts/outfit-latin-700-normal.woff2/fonts/outfit-latin-700-normal.woff... https://stelgano.com/fonts/outfit-latin-700-normal.woff2 — 200 — 15.5 KiB — 119 ms — h3https://stelgano.com/fonts/outfit-latin-300-normal.woff2/fonts/outfit-latin-300-normal.woff... https://stelgano.com/fonts/outfit-latin-300-normal.woff2 — 200 — 14.7 KiB — 117 ms — h3https://stelgano.com/fonts/jetbrains-mono-latin-400-normal.woff2/fonts/jetbrains-mono-latin-400-nor... https://stelgano.com/fonts/jetbrains-mono-latin-400-normal.woff2 — 200 — 21.8 KiB — 111 ms — h3https://stelgano.com/fonts/inter-latin-500-normal.woff2/fonts/inter-latin-500-normal.woff2 https://stelgano.com/fonts/inter-latin-500-normal.woff2 — 200 — 25.4 KiB — 120 ms — h3https://stelgano.com/fonts/inter-latin-400-normal.woff2/fonts/inter-latin-400-normal.woff2 https://stelgano.com/fonts/inter-latin-400-normal.woff2 — 200 — 24.2 KiB — 118 ms — h3https://stelgano.com/fonts/outfit-latin-600-normal.woff2/fonts/outfit-latin-600-normal.woff... https://stelgano.com/fonts/outfit-latin-600-normal.woff2 — 200 — 14.9 KiB — 117 ms — h3https://stelgano.com/fonts/jetbrains-mono-latin-500-normal.woff2/fonts/jetbrains-mono-latin-500-nor... https://stelgano.com/fonts/jetbrains-mono-latin-500-normal.woff2 — 200 — 22.4 KiB — 110 ms — h3https://stelgano.com/images/favicon-96x96.png/images/favicon-96x96.png https://stelgano.com/images/favicon-96x96.png — 200 — 4.2 KiB — 33 ms — h3
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Image Optimization
1 images, 0 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

1

Total Size

0 KB

1 missing dimensions
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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