Performance
· 28 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
2.46 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
11.13 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
670 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.
3.22 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.
11.13 s
Page Load Progression
DPage Weight BudgetAction2.1 MB transferred, 61 requestsFIX
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.
Source: web.dev
DJS Execution CostAction3250ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.jcl.energy/ | 761ms | 127ms | 2ms | 1st |
| Unattributable | 565ms | 127ms | 0ms | 1st |
| https://edge.fullstory.com/s/fs.js?org=o-24MHWM-na1 | 538ms | 402ms | 22ms | 3rd |
| https://js.hs-analytics.net/analytics/1789959900000/24421275.js | 518ms | 353ms | 9ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-E3GZP5Q418 | 304ms | 265ms | 37ms | 3rd |
| https://www.jcl.energy/_nuxt/C3i5kfut.js | 278ms | 221ms | 0ms | 1st |
| https://www.googletagmanager.com/gtag/js?id=AW-17012445944 | 162ms | 131ms | 30ms | 3rd |
| https://js.hscollectedforms.net/collectedforms.js | 69ms | 57ms | 6ms | 3rd |
| https://www.jcl.energy/_nuxt/DBvxyBpE.js | 55ms | 52ms | 0ms | 1st |
DJS BundlesAction30 scripts, 346 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=AW-17012445944&cx=c>m=4e69g1 | 146 KB | 110 KB (76%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-E3GZP5Q418 | 162 KB | 68 KB (42%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-17012445944 | 146 KB | 68 KB (47%) | ✓ | 3rd |
| https://www.jcl.energy/_nuxt/CgbXtZQp.js | 72 KB | 46 KB (69%) | ✓ | 1st |
| https://edge.fullstory.com/s/fs.js?org=o-24MHWM-na1 | 80 KB | 30 KB (38%) | ✓ | 3rd |
| https://www.jcl.energy/_nuxt/B4IKQn3F.js | 86 KB | 24 KB (28%) | ✓ | 1st |
| https://www.jcl.energy/_nuxt/CLmx7Oqj.js | 14 KB | — | ✓ | 1st |
| https://www.jcl.energy/_nuxt/BCFFW011.js | 2 KB | — | ✓ | 1st |
| https://www.jcl.energy/_nuxt/8gBTCIwE.js | 2 KB | — | ✓ | 1st |
| https://www.jcl.energy/_nuxt/CxiGgwzJ.js | 11 KB | — | ✓ | 1st |
Consider code splitting or tree shaking to reduce unused code.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
Consider code splitting or tree shaking to reduce unused code.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
Consider code splitting or tree shaking to reduce unused code.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
Consider code splitting or tree shaking to reduce unused code.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
Consider code splitting or tree shaking to reduce unused code.
This bundle has high unused code — code-split or tree-shake to ship only what executes.
Source: web.dev / Lighthouse coverage
DPage Weight InventoryAction61 resources · 2.1 MB · 346 KB savings availableFIX
~345.9 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 61 resources | 2.1 MiB | ||||||
BImage Optimization7 images, 0 KB saveableREVIEW
BHTTP/3 (QUIC)HTTP/3 not advertisedREVIEW
BServer-Timing ObservabilityNo Server-Timing header foundREVIEW
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
BHTTP Cachingpublic, max-age=0, s-maxage=60, must-revalidateREVIEW
public, max-age=0, s-maxage=60, must-revalidate
| Directive | Value | Meaning |
|---|---|---|
| public | — | Any cache may store this response |
| max-age | 0 | Cache for 0 seconds |
| s-maxage | 60 | CDN caches for 1 minute |
| must-revalidate | — | Must recheck with server after expiry |
AThird-Party Impact30% third-party, 0 ms blockingPASS
A+Text CompressionAll text resources are compressedPASS
A+Font Loading5 fonts (134 KB)PASS
Web fonts
5
134 KB total
Render-blocking
0
of 5
Dominant font-display
swap
Most common across fonts
Font loading timeline
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+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource Hints3 hints, 0 missing preconnectsPASS
Current Resource Hints
3 resource hints configured
A+Document CompressionDocument response uses brotliPASS
A+Asset CompressionAll 1 asset host use brotliPASS
A+LCP Image PreloadLCP preload audit not availablePASS
A+Main HTML Cache-ControlMain HTML max-age=0 (≤ 5min) is appropriatePASS
A+Server Response Intelligence2 server-response signal(s) detectedPASS
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
AJavaScript Blocking1 JS blocking issue(s) detectedPASS
ACSS Performance Depth1 CSS depth issue(s) detectedPASS
Network Waterfall61 requests over 3649msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
edge.fullstory.com edge.fullstory.com | Other | 538ms | 80 KB | 38% | €6/mo | Costly |
HubSpot Analytics js.hs-analytics.net | Analytics | 518ms | 43 KB | — | €6/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 304ms | 162 KB | 42% | €3/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 162ms | 146 KB | 47% | €2/mo | Optional |
js.hscollectedforms.net js.hscollectedforms.net | Other | 69ms | 27 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- edge.fullstory.com adds 538ms and costs ~€6/month
- HubSpot Analytics adds 518ms and costs ~€6/month
- Google Tag Manager adds 304ms and costs ~€3/month
49% of JavaScript execution time comes from third-party scripts.
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
edge.fullstory.com takes 538ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
HubSpot Analytics takes 518ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
Google Tag Manager takes 304ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.
This script has high main-thread execution time — optimize hot paths or defer.
Source: web.dev
Real-User Performance (CrUX)Field metrics from the Chrome User Experience ReportINFO
Chrome User Experience (CrUX)
Real-user metrics from the Chrome UX Report (2026-08-23 — 2026-09-19)
LCP (p75)
2602 ms
72% good
INP (p75)
0 ms
0% good
CLS (p75)
0.000
100% good
FCP (p75)
1607 ms
TTFB (p75)
0 ms
Image Optimization15 images, 501 KB total, 363 KB wastedINFO
Image Optimization Audit
Total Images
15
Total Size
501 KB
Oversized
3
Wasted
363 KB