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https://www.storyblok.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
82
GRADE
B
FIX
1
REVIEW
6
PASS
5
INFO
2

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

Mobile Desktop
88
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
96
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.
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.

906 ms

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

2.14 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

6 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.005

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

1.18 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.

2.14 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
5 PASS 6 REVIEW 1 FIX
D
Third-Party Impact
Action
65% third-party, 0 ms blocking
FIX
65% third-party, 0 ms blocking
Warning::
Third-party code accounts for 65% of page weight (737.9 KiB of 1.1 MiB)
Info::
Third-party blocking time is low (0 ms)
35%
65%
First-party Third-party
B
Page Weight Budget
1.1 MB transferred, 101 requests
REVIEW
1.1 MB transferred, 101 requests
Info::
Page weighs 3.3 MB (1.1 MB transferred)
Warning::
JavaScript is 525 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 525 KB
Warning::
101 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 0.23 g CO2 per page load
1.1 MB / 2.4 MB budget
1.1 MB transferred
101 requests
0.23 g CO2 per page load
JavaScript 525.4 KiB 46%
Images 322.1 KiB 28%
Fonts 161.4 KiB 14%
CSS 68.7 KiB 6%
HTML 52.7 KiB 5%
Other 2.1 KiB 0%
Other 1.7 KiB 0%
Other 971 B 0%
Other 476 B 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Under budget

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

B
Image Optimization
44 images, 0 KB saveable
REVIEW
44 images, 0 KB saveable
Info::
All images are well-optimized
44 images 322 KB
0 oversized -0 KB
37 legacy format
0 missing dimensions CLS risk
C
JS Execution Cost
Action
1095ms total JS execution
REVIEW
1095ms total JS execution
Warning::
https://www.storyblok.com/: 482ms CPU time
Warning::
Unattributable: 296ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-HWTG...: 167ms CPU time
Info::
https://www.storyblok.com/_astro/page.k449a2wJ.js: 88ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=AW-674...: 62ms CPU time
Info::
Third-party scripts: 525ms (48% of total)

Main Thread Breakdown

Other 36% Script Evaluation 25% Style & Layout 24% Rendering 8% Script Parsing & Compilation 5%
ScriptTotalScriptingParse/CompileParty
https://www.storyblok.com/482ms9ms2ms1st
Unattributable296ms31ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=G-HWTGCECK5C167ms67ms41ms3rd
https://www.storyblok.com/_astro/page.k449a2wJ.js88ms77ms0ms1st
https://www.googletagmanager.com/gtag/js?id=AW-674753115&cx=c&gtm=4e6461h262ms53ms9ms3rd
C
JS Bundles
Action
30 scripts, 170 KB unused
REVIEW
30 scripts, 170 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-HWTG...: 65 KB unused (39%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=AW-674...: 60 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://eu.i.posthog.com/static/array.js: 45 KB unused (70%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 170 KB
170 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-HWTGCECK5C169 KB65 KB (39%)✓3rd
https://www.googletagmanager.com/gtag/js?id=AW-674753115&cx=c&gtm=4e6461h2147 KB60 KB (41%)✓3rd
https://eu.i.posthog.com/static/array.js65 KB45 KB (70%)✓3rd
https://www.storyblok.com/_astro/exports.CuIIb5En.js13 KB—✓1st
https://www.storyblok.com/_astro/page.k449a2wJ.js37 KB—✓1st
https://www.storyblok.com/_astro/Base.astro_astro_type_script_index_0_lang.BfWP2xCS.js6 KB—✓1st
https://www.storyblok.com/_astro/ConsentNotice.astro_astro_type_script_index_0_lang.5VazJZjp.js2 KB—✓1st
https://www.storyblok.com/_astro/js.cookie.ZV3VVXDq.js2 KB—✓1st
https://www.storyblok.com/_astro/tracking.B4FkHCOy.js36 KB—✓1st
https://www.storyblok.com/_astro/websiteConfig.CdTN-17h.js2 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

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

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

C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

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::
ETag present — enables conditional (304) responses
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+
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 (161 KB)
PASS
4 fonts (161 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

161 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 FCP 906 ms LCP 2.1 shttps://www.storyblok.com/fonts/ABCMarfa-Regular.woff2ABCMarfa-Regular.woff2 https://www.storyblok.com/fonts/ABCMarfa-Regular.woff2 — 37.6 KiB — 0 ms — font-display: swaphttps://www.storyblok.com/fonts/ABCMarfa-Bold.woff2ABCMarfa-Bold.woff2 https://www.storyblok.com/fonts/ABCMarfa-Bold.woff2 — 41.9 KiB — 0 ms — font-display: swaphttps://www.storyblok.com/fonts/ABCMarfa-Black.woff2ABCMarfa-Black.woff2 https://www.storyblok.com/fonts/ABCMarfa-Black.woff2 — 40.3 KiB — 0 ms — font-display: swaphttps://www.storyblok.com/fonts/ABCMarfa-Medium.woff2ABCMarfa-Medium.woff2 https://www.storyblok.com/fonts/ABCMarfa-Medium.woff2 — 41.6 KiB — 0 ms — font-display: swap
ABCMarfa-Regular.woff2 woff2 swap
Size 38 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ABCMarfa-Bold.woff2 woff2 swap
Size 42 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ABCMarfa-Black.woff2 woff2 swap
Size 40 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
ABCMarfa-Medium.woff2 woff2 swap
Size 42 KB
Load time 0 ms
Start 0 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+
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
Network Waterfall
101 requests over 0ms
INFO

Performance analysis not available for this result.

Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
48% of JavaScript execution is third-party
First-party Third-party 525ms · 315KB · €6/mo
Unattributable
Other
Costly
Execution 296ms
Transfer 0 KB
Monthly Cost €3/mo
Google Tag Manager
Tag Manager
Optional
Execution 167ms
Transfer 169 KB
Unused 39%
Monthly Cost €2/mo
Google Tag Manager
Tag Manager
Optional
Execution 62ms
Transfer 147 KB
Unused 41%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Unattributable adds 296ms and costs ~€3/month

48% of JavaScript execution time comes from third-party scripts.

Why this matters

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

Unattributable takes 296ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

How third-party costs are calculated

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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