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https://Svennouwen.nl

Performance

· 26 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
94
GRADE
A
FIX
1
REVIEW
5
PASS
17
INFO
3

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

Mobile Desktop
96
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
98
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.

1.22 s

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

2.72 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.

0.000

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

2.02 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.

2.72 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
26
17 PASS 5 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-store
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

no-store

DirectiveValueMeaning
no-store—Never cache this response
B
Image Optimization
4 images, 0 KB saveable
REVIEW
4 images, 0 KB saveable
Info::
All images are well-optimized
4 images 142 KB
0 oversized -0 KB
4 legacy format
0 missing dimensions CLS risk
B
JS Execution Cost
724ms total JS execution
REVIEW
724ms total JS execution
Warning::
https://svennouwen.nl/: 357ms CPU time
Info::
https://svennouwen.nl/wp-includes/js/jquery/jquery...: 187ms CPU time
Info::
Unattributable: 181ms CPU time

Main Thread Breakdown

Script Evaluation 30% Other 26% Style & Layout 24% Parse HTML & CSS 9% Script Parsing & Compilation 6%
ScriptTotalScriptingParse/CompileParty
https://svennouwen.nl/357ms24ms8ms1st
https://svennouwen.nl/wp-includes/js/jquery/jquery.min.js?ver=3.7.1187ms144ms9ms1st
Unattributable181ms7ms0ms1st
B
HTTP/3 (QUIC)
HTTP/3 not advertised
REVIEW
HTTP/3 not advertised
Info::
HTTP/3 (QUIC) is not advertised
HTTP/3 isn't advertised via Alt-Svc and the worker didn't negotiate h3. HTTP/3 reduces handshake latency (1-RTT instead of 2-3 RTTs) and is more resilient on lossy connections. Most modern CDNs (Cloudflare, Fastly, AWS CloudFront, Google Cloud CDN) support HTTP/3 with a single config switch -- consider enabling for mobile-heavy workloads.
C
Document Compression
Action
Document response served uncompressed
REVIEW
Document response served uncompressed
Info::
Main HTML response has no Content-Encoding (uncompressed)
The main HTML document is served without compression. The Text Compression section above lists the broader picture; for the main response specifically, even gzip would shave ~70-80% off most text payloads.
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.
A+
Page Weight Budget
393 KB transferred, 26 requests
PASS
393 KB transferred, 26 requests
Info::
Page weighs 1.0 MB (393 KB transferred)
Info::
26 HTTP requests
Info::
Estimated 0.08 g CO2 per page load
393 KB / 2.4 MB budget
393 KB transferred
26 requests
0.08 g CO2 per page load
JavaScript 143.1 KiB 36%
Images 142.0 KiB 36%
Fonts 48.3 KiB 12%
CSS 32.0 KiB 8%
HTML 26.6 KiB 7%
Other 1.2 KiB 0%
Other 170 B 0%
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+
Font Loading
4 fonts (48 KB)
PASS
4 fonts (48 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

48 KB total

Render-blocking

0

of 4

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 2.0 s 2.5 s FCP 1.2 s LCP 2.7 shttps://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-400-normal.woff2?v=20260930plus-jakarta-sans-latin... https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-400-normal.woff2?v=20260930 — 11.8 KiB — 32 ms — font-display: swaphttps://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-700-normal.woff2?v=20260930plus-jakarta-sans-latin... https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-700-normal.woff2?v=20260930 — 12.2 KiB — 59 ms — font-display: swaphttps://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-500-normal.woff2?v=20260930plus-jakarta-sans-latin... https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-500-normal.woff2?v=20260930 — 12.2 KiB — 32 ms — font-display: swaphttps://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-600-normal.woff2?v=20260930plus-jakarta-sans-latin... https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-600-normal.woff2?v=20260930 — 12.1 KiB — 33 ms — font-display: swap
plus-jakarta-sans-latin... woff2 swap
Size 12 KB
Load time 32 ms
Start 952 ms
Risk FOUT — text flashes from fallback to web font
plus-jakarta-sans-latin... woff2 swap
Size 12 KB
Load time 59 ms
Start 953 ms
Risk FOUT — text flashes from fallback to web font
plus-jakarta-sans-latin... woff2 swap
Size 12 KB
Load time 32 ms
Start 1.1 s
Risk FOUT — text flashes from fallback to web font
plus-jakarta-sans-latin... woff2 swap
Size 12 KB
Load time 33 ms
Start 1.1 s
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
12 scripts, 32 KB unused
PASS
12 scripts, 32 KB unused
Warning::
https://svennouwen.nl/wp-content/themes/jupiterx/l...: 32 KB unused (84%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 32 KB
32 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://svennouwen.nl/wp-content/themes/jupiterx/lib/assets/dist/js/frontend.min.js?ver=4.61.039 KB32 KB (84%)✓1st
https://svennouwen.nl/wp-includes/js/jquery/jquery.min.js?ver=3.7.130 KB—✓1st
https://svennouwen.nl/wp-content/themes/jupiterx/lib/assets/dist/js/utils.min.js?ver=4.61.00 KB—✓1st
https://svennouwen.nl/wp-includes/js/underscore.min.js?ver=1.13.87 KB—✓1st
https://svennouwen.nl/wp-content/plugins/elementor/assets/js/webpack.runtime.min.js?ver=4.3.20 KB—✓1st
https://svennouwen.nl/wp-content/plugins/elementor/assets/js/frontend-modules.min.js?ver=4.3.216 KB—✓1st
https://svennouwen.nl/wp-includes/js/jquery/ui/core.min.js?ver=1.14.27 KB—✓1st
https://svennouwen.nl/wp-content/plugins/elementor/assets/js/frontend.min.js?ver=4.3.219 KB—✓1st
https://svennouwen.nl/wp-includes/js/wp-util.min.js?ver=7.1.21 KB—✓1st
https://svennouwen.nl/wp-content/plugins/elementor/assets/js/chunks/background-slideshow.min.js?ver=4.3.28 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+
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
2 hints, 0 missing preconnects
PASS
2 hints, 0 missing preconnects
Info::
Page uses 2 resource hint(s)

Current Resource Hints

preconnect
—
preload
2
dns-prefetch
—
prefetch
—

2 resource hints configured

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 uses no-store -- correct for sensitive/dynamic content
PASS
Main HTML uses no-store -- correct for sensitive/dynamic content
Info::
Main HTML uses no-store -- correct for sensitive/dynamic content
Got: no-store
A+
Server Response Intelligence
1 server-response signal(s) detected
PASS
1 server-response signal(s) detected
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+
Page Weight Inventory
26 resources · 393 KB · 32 KB savings available
PASS
26 resources · 393 KB · 32 KB savings available
Info::
Within 1MB page-weight target
Got: 393 KB
26 resources · 393.4 KiB · 0 third-party Within 1MB page-weight target
Image 36% · 143.2 KiB
JavaScript 36% · 143.1 KiB
Font 12% · 48.3 KiB
CSS 8% · 32.0 KiB
Document 7% · 26.6 KiB
Other 0% · 170 B

~32.4 KiB of savings available

Remove unused JavaScript: 32.4 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+
JavaScript Blocking
No render-blocking JS or document.write usage detected
PASS
No render-blocking JS or document.write usage detected
Info::
No JavaScript blocking issues detected
A+
CSS Performance Depth
No CSS performance depth issues detected
PASS
No CSS performance depth issues detected
Info::
No CSS performance depth issues 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: Combell

Asset Compression
No text asset hosts to measure
INFO
No text asset hosts to measure
Info::
No third-party or subdomain host served enough text assets to measure
Asset compression is measured per host, from one HEAD request against a sampled resource. Pages that serve all their JS and CSS from the document's own origin are covered by the document compression check instead.
Network Waterfall
26 requests over 1201ms
INFO
0 ms 500 ms 1.0 s 1.5 s 2.0 s 2.5 s FCP 1.2 s LCP 2.7 shttps://svennouwen.nl// https://svennouwen.nl/ — 200 — 26.6 KiB — 924 ms — h2https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-400-normal.woff2?v=20260930/wp-content/uploads/fonts/plus-jaka... https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-400-normal.woff2?v=20260930 — 200 — 11.8 KiB — 32 ms — h2https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-700-normal.woff2?v=20260930/wp-content/uploads/fonts/plus-jaka... https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-700-normal.woff2?v=20260930 — 200 — 12.2 KiB — 59 ms — h2https://svennouwen.nl/wp-content/uploads/jupiterx/compiler/jupiterx/9ff7467.css?ver=4.61.0/wp-content/uploads/jupiterx/compil... https://svennouwen.nl/wp-content/uploads/jupiterx/compiler/jupiterx/9ff7467.css?ver=4.61.0 — 200 — 21.0 KiB — 59 ms — h2https://svennouwen.nl/wp-content/uploads/jupiterx/compiler/jupiterx-elements-dynamic-styles/61836c7.css?ver=4.61.0/wp-content/uploads/jupiterx/compil... https://svennouwen.nl/wp-content/uploads/jupiterx/compiler/jupiterx-elements-dynamic-styles/61836c7.css?ver=4.61.0 — 200 — 3.7 KiB — 35 ms — h2https://svennouwen.nl/wp-content/plugins/elementor/assets/css/frontend.min.css?ver=4.3.2/wp-content/plugins/elementor/asset... https://svennouwen.nl/wp-content/plugins/elementor/assets/css/frontend.min.css?ver=4.3.2 — 200 — 7.3 KiB — 38 ms — h2https://svennouwen.nl/wp-content/uploads/2026/09/sven-signature-gradient.svg/wp-content/uploads/2026/09/sven-si... https://svennouwen.nl/wp-content/uploads/2026/09/sven-signature-gradient.svg — 200 — 6.6 KiB — 61 ms — h2https://svennouwen.nl/wp-content/uploads/2026/09/ephemora-icon-300x300.png/wp-content/uploads/2026/09/ephemor... https://svennouwen.nl/wp-content/uploads/2026/09/ephemora-icon-300x300.png — 200 — 108.8 KiB — 89 ms — h2https://svennouwen.nl/wp-content/uploads/2026/09/pinned-icon-300x300.png/wp-content/uploads/2026/09/pinned-... https://svennouwen.nl/wp-content/uploads/2026/09/pinned-icon-300x300.png — 200 — 22.4 KiB — 91 ms — h2https://svennouwen.nl/wp-includes/js/jquery/jquery.min.js?ver=3.7.1/wp-includes/js/jquery/jquery.min.j... https://svennouwen.nl/wp-includes/js/jquery/jquery.min.js?ver=3.7.1 — 200 — 29.9 KiB — 77 ms — h2https://svennouwen.nl/wp-content/themes/jupiterx/lib/assets/dist/js/utils.min.js?ver=4.61.0/wp-content/themes/jupiterx/lib/ass... https://svennouwen.nl/wp-content/themes/jupiterx/lib/assets/dist/js/utils.min.js?ver=4.61.0 — 200 — 485 B — 76 ms — h2https://svennouwen.nl/wp-includes/js/underscore.min.js?ver=1.13.8/wp-includes/js/underscore.min.js?v... https://svennouwen.nl/wp-includes/js/underscore.min.js?ver=1.13.8 — 200 — 7.4 KiB — 76 ms — h2https://svennouwen.nl/wp-content/themes/jupiterx/lib/assets/dist/js/frontend.min.js?ver=4.61.0/wp-content/themes/jupiterx/lib/ass... https://svennouwen.nl/wp-content/themes/jupiterx/lib/assets/dist/js/frontend.min.js?ver=4.61.0 — 200 — 39.0 KiB — 82 ms — h2https://svennouwen.nl/wp-content/plugins/elementor/assets/js/webpack.runtime.min.js?ver=4.3.2/wp-content/plugins/elementor/asset... https://svennouwen.nl/wp-content/plugins/elementor/assets/js/webpack.runtime.min.js?ver=4.3.2 — 200 — 334 B — 82 ms — h2https://svennouwen.nl/wp-content/plugins/elementor/assets/js/frontend-modules.min.js?ver=4.3.2/wp-content/plugins/elementor/asset... https://svennouwen.nl/wp-content/plugins/elementor/assets/js/frontend-modules.min.js?ver=4.3.2 — 200 — 16.2 KiB — 95 ms — h2https://svennouwen.nl/wp-includes/js/jquery/ui/core.min.js?ver=1.14.2/wp-includes/js/jquery/ui/core.min.... https://svennouwen.nl/wp-includes/js/jquery/ui/core.min.js?ver=1.14.2 — 200 — 6.6 KiB — 95 ms — h2https://svennouwen.nl/wp-content/plugins/elementor/assets/js/frontend.min.js?ver=4.3.2/wp-content/plugins/elementor/asset... https://svennouwen.nl/wp-content/plugins/elementor/assets/js/frontend.min.js?ver=4.3.2 — 200 — 18.6 KiB — 95 ms — h2https://svennouwen.nl/wp-includes/js/wp-util.min.js?ver=7.1.2/wp-includes/js/wp-util.min.js?ver=... https://svennouwen.nl/wp-includes/js/wp-util.min.js?ver=7.1.2 — 200 — 984 B — 95 ms — h2https://svennouwen.nl/koko-analytics-collect.php/koko-analytics-collect.php https://svennouwen.nl/koko-analytics-collect.php — 200 — 170 B — 44 ms — h2https://svennouwen.nl/wp-content/uploads/2026/04/Download_on_the_App_Store_Badge_US-UK_RGB_blk_092917.svg/wp-content/uploads/2026/04/Downloa... https://svennouwen.nl/wp-content/uploads/2026/04/Download_on_the_App_Store_Badge_US-UK_RGB_blk_092917.svg — 200 — 4.2 KiB — 35 ms — h2https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-500-normal.woff2?v=20260930/wp-content/uploads/fonts/plus-jaka... https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-500-normal.woff2?v=20260930 — 200 — 12.2 KiB — 32 ms — h2https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-600-normal.woff2?v=20260930/wp-content/uploads/fonts/plus-jaka... https://svennouwen.nl/wp-content/uploads/fonts/plus-jakarta-sans-latin-600-normal.woff2?v=20260930 — 200 — 12.1 KiB — 33 ms — h2https://svennouwen.nl/wp-content/plugins/elementor/assets/js/chunks/background-slideshow.min.js?ver=4.3.2/wp-content/plugins/elementor/asset... https://svennouwen.nl/wp-content/plugins/elementor/assets/js/chunks/background-slideshow.min.js?ver=4.3.2 — 200 — 8.0 KiB — 34 ms — h2https://svennouwen.nl/wp-content/plugins/elementor/assets/js/chunks/background-video.min.js?ver=4.3.2/wp-content/plugins/elementor/asset... https://svennouwen.nl/wp-content/plugins/elementor/assets/js/chunks/background-video.min.js?ver=4.3.2 — 200 — 8.4 KiB — 34 ms — h2https://svennouwen.nl/wp-content/plugins/elementor/assets/js/chunks/text-editor.min.js?ver=4.3.2/wp-content/plugins/elementor/asset... https://svennouwen.nl/wp-content/plugins/elementor/assets/js/chunks/text-editor.min.js?ver=4.3.2 — 200 — 7.3 KiB — 35 ms — h2https://svennouwen.nl/wp-content/uploads/2026/04/cropped-New-styling-for-Sven-08-1-32x32.png/wp-content/uploads/2026/04/cropped... https://svennouwen.nl/wp-content/uploads/2026/04/cropped-New-styling-for-Sven-08-1-32x32.png — 200 — 1.2 KiB — 29 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Image Optimization
5 images, 54 KB total, 36 KB wasted
INFO

Image Optimization Audit

Total Images

5

Total Size

54 KB

Oversized

2

Wasted

36 KB

3 missing lazy loading
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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