https://www.rhenen.nl
Performance
· 23 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.SCORE
92
GRADE
A
FIX
0
REVIEW
5
PASS
15
INFO
3
Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
93
100
92
100
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
418 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.49 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.
0.089
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
637 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.
1.49 s
Page Load Progression
Checks
2315 PASS 5 REVIEW
BPage Weight Budget1.2 MB transferred, 88 requestsREVIEW
Page Weight Budget
1.2 MB transferred, 88 requests
1.2 MB transferred, 88 requests
Info::
Page weighs 1.7 MB (1.2 MB transferred)
Info::
88 HTTP requests
Info::
Estimated 0.25 g CO2 per page load
1.2 MB transferred
88 requests
0.25 g CO2 per page load
Images 923.1 KiB 76%
CSS 94.5 KiB 8%
Fonts 81.1 KiB 7%
JavaScript 75.7 KiB 6%
HTML 20.6 KiB 2%
Other 18.2 KiB 1%
Other 2.4 KiB 0%
Other 191 B 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Under budget
CImage OptimizationAction8 images, 0 KB saveableREVIEW
Image Optimization
Action8 images, 0 KB saveable
8 images, 0 KB saveable
Warning::
https://www.rhenen.nl/fileadmin/user_upload/Logo_R... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.rhenen.nl/fileadmin/_processed_/0/7/cs... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://www.rhenen.nl/fileadmin/_processed_/d/4/cs... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
8 images 923 KB
0 oversized -0 KB
6 legacy format
3 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
BHTTP/3 (QUIC)HTTP/3 not advertisedREVIEW
HTTP/3 (QUIC)
HTTP/3 not advertised
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.
BServer-Timing ObservabilityNo Server-Timing header foundREVIEW
Server-Timing Observability
No Server-Timing header found
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.
BHTTP Cachingno-cacheREVIEW
HTTP Caching
no-cache
no-cache
Info::
Cache-Control header is set
Got: no-cache
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control
no-cache
| Directive | Value | Meaning |
|---|---|---|
| no-cache | — | Cache but always revalidate first |
A+Third-Party Impact11% third-party, 0 ms blockingPASS
Third-Party Impact
11% third-party, 0 ms blocking
11% third-party, 0 ms blocking
Info::
Third-party code accounts for 11% of page weight (139.3 KiB of 1.2 MiB)
Info::
Third-party blocking time is low (0 ms)
89%
First-party Third-party
A+Text CompressionAll text resources are compressedPASS
Text Compression
All text resources are compressed
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+JS Execution Cost260ms total JS executionPASS
JS Execution Cost
260ms total JS execution
260ms total JS execution
Info::
https://www.rhenen.nl/: 181ms CPU time
Info::
Unattributable: 79ms CPU time
Main Thread Breakdown
Style & Layout 37% Other 36% Script Evaluation 11% Rendering 9% Parse HTML & CSS 5%
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.rhenen.nl/ | 181ms | 1ms | 0ms | 1st |
| Unattributable | 79ms | 2ms | 0ms | 1st |
A+Font Loading5 fonts (81 KB)PASS
Font Loading
5 fonts (81 KB)
5 fonts (81 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)
Web fonts
5
81 KB total
Render-blocking
0
of 5
Dominant font-display
swap
Most common across fonts
Font loading timeline
Transfer FOIT (block) FOUT (swap)
open-sans-v15-latin-reg... woff2 swap
Size 14 KB
Load time 29 ms
Start 397 ms
Risk FOUT — text flashes from fallback to web font
open-sans-v15-latin-600... woff2 swap
Size 15 KB
Load time 31 ms
Start 398 ms
Risk FOUT — text flashes from fallback to web font
open-sans-v15-latin-700... woff2 swap
Size 15 KB
Load time 31 ms
Start 398 ms
Risk FOUT — text flashes from fallback to web font
x-font-ttf;charset=utf-... unknown swap
Size 13 KB
Load time 19 ms
Start 483 ms
Risk FOUT — text flashes from fallback to web font
font-woff;charset=utf-8... woff swap
Size 25 KB
Load time 19 ms
Start 483 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 ~11 KB and ~22 ms
A+JS Bundles17 scripts, 0 KB unusedPASS
JS Bundles
17 scripts, 0 KB unused
17 scripts, 0 KB unused
0 KB unused JavaScript
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.rhenen.nl/typo3temp/assets/js/573f81248d18dd4b567e70fe98a30b75.js?1794364281 | 1 KB | — | ✓ | 1st |
| https://cdn-eu.readspeaker.com/script/6093/webReader/webReader.js?pids=wr¬ools=1 | 28 KB | — | ✓ | 3rd |
| https://www.rhenen.nl/typo3temp/assets/js/0f851906d0fb8bbe408c0ec9ef59dfcc.js?1794364281 | 1 KB | — | ✓ | 1st |
| https://www.rhenen.nl/typo3temp/assets/js/d5d38c9b55b605775d83fc95c55d3360.js?1794364281 | 1 KB | — | ✓ | 1st |
| https://www.rhenen.nl/_assets/6c3bf359f8df9d9222347f37e2814501/JavaScript/OpenGemeentenSiteSearch-PageHeader-Search.min.js?1794359036 | 1 KB | — | ✓ | 1st |
| https://www.rhenen.nl/_assets/6c3bf359f8df9d9222347f37e2814501/JavaScript/OpenGemeentenSiteSearch-Suggest.min.js?1794359036 | 2 KB | — | ✓ | 1st |
| https://www.rhenen.nl/_assets/f52859db1e4f013bae2a279b52772e55/Js/OpenGemeentenCeFeatureCollapsible.min.js?1794359036 | 2 KB | — | ✓ | 1st |
| https://www.rhenen.nl/_assets/317130fbcbb12622b6e28e3bfff3cb16/Js/OpenGemeentenSite-Focusable.min.js?1794359036 | 1 KB | — | ✓ | 1st |
| https://www.rhenen.nl/_assets/317130fbcbb12622b6e28e3bfff3cb16/Js/OpenGemeentenSite-FragmentScroll.min.js?1794359036 | 1 KB | — | ✓ | 1st |
| https://www.rhenen.nl/_assets/317130fbcbb12622b6e28e3bfff3cb16/Js/OpenGemeentenSite-Media.min.js?1794359036 | 2 KB | — | ✓ | 1st |
A+Resource CachingAll resources properly cachedPASS
Resource Caching
All resources properly cached
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+Critical Rendering PathNo render-blocking resourcesPASS
Critical Rendering Path
No render-blocking resources
No render-blocking resources
Info::
No render-blocking resources detected
A+Resource HintsNo optimization neededPASS
Resource Hints
No optimization needed
No optimization needed
Info::
No resource hint issues
A+Document CompressionDocument response uses brotliPASS
Document Compression
Document response uses brotli
Document 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.
AAsset Compression1 of 1 asset host still on gzipPASS
Asset Compression
1 of 1 asset host still on gzip
1 of 1 asset host still on gzip
Info::
cdn-eu.readspeaker.com serves assets with gzip; brotli would be ~20% smaller (assets: 3)
Every current browser accepts brotli. On a CDN this is a per-pull-zone toggle (Cloudflare, Fastly, CloudFront, CDN77, Bunny all expose it); on an origin it needs the brotli module (nginx-brotli, Apache mod_brotli). The saving lands on the assets this host serves, not on the HTML document -- the document's own encoding is reported separately.
Got: cdn-eu.readspeaker.com (text/css)
A+LCP Image PreloadLCP preload audit not availablePASS
LCP Image Preload
LCP preload audit not available
LCP preload audit not available
Info::
LCP image preload audit not available for this scan
A+Main HTML Cache-ControlMain HTML uses no-cache -- safe revalidate-on-request policyPASS
Main HTML Cache-Control
Main HTML uses no-cache -- safe revalidate-on-request policy
Main HTML uses no-cache -- safe revalidate-on-request policy
Info::
Main HTML uses no-cache -- safe revalidate-on-request policy
Got: no-cache
A+Server Response Intelligence2 server-response signal(s) detectedPASS
Server Response Intelligence
2 server-response signal(s) detected
2 server-response signal(s) detected
Info::
`Vary` header declared: Accept-Encoding
The page declares a `Vary` header, telling downstream caches which request headers the response varies on. Critical for content-negotiated responses (compression, language, cookies, device class).
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.
APage Weight Inventory88 resources · 1.2 MB · 0 KB savings availablePASS
Page Weight Inventory
88 resources · 1.2 MB · 0 KB savings available
88 resources · 1.2 MB · 0 KB savings available
Warning::
Page weight 1.2 MB exceeds 1 MB target by 192 KB
Got: 1.2 MB Expected: ≤ 1 MB
Info::
13 third-party resources (11% of weight)
Info::
1 resources over 200KB
88 resources · 1.2 MiB · 13 third-party 191.8 KiB over 1MB target
Image 77% · 941.4 KiB
CSS 8% · 94.5 KiB
Font 7% · 81.1 KiB
JavaScript 6% · 75.7 KiB
Document 2% · 22.9 KiB
Other 0% · 275 B
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 88 resources | 1.2 MiB | ||||||
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
Whether the site is served from green-energy infrastructure
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall88 requests over 955msINFO
Network Waterfall
88 requests over 955ms
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Real-User Performance (CrUX)Field metrics from the Chrome User Experience ReportINFO
Real-User Performance (CrUX)
Field metrics from the Chrome User Experience Report
Chrome User Experience (CrUX)
Real-user metrics from the Chrome UX Report (2026-10-14 — 2026-11-10)
LCP (p75)
1082 ms
95% good
INP (p75)
70 ms
99% good
CLS (p75)
0.000
98% good
FCP (p75)
1006 ms
TTFB (p75)
486 ms
This origin passes Core Web Vitals assessment
Image Optimization5 images, 403 KB total, 0 KB wastedINFO
Image Optimization
5 images, 403 KB total, 0 KB wasted
Image Optimization Audit
Total Images
5
Total Size
403 KB
5 missing dimensions 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.