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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
73
GRADE
C
FIX
4
REVIEW
3
PASS
5
INFO
2

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

Mobile Desktop
64
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
85
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
96
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.

1.25 s

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

1.68 s

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

493 ms

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

0.013

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

2.60 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.

5.25 s

Page Load Progression

967 ms
1.9 s
2.9 s
3.9 s
4.8 s
5.8 s
6.8 s
7.7 s
Checks
14
5 PASS 3 REVIEW 4 FIX
F
Page Weight Budget
Action
4.8 MB transferred, 226 requests
FIX
4.8 MB transferred, 226 requests
Critical::
Page weighs 15.5 MB (4.8 MB transferred)
Warning::
JavaScript is 3.2 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 3.2 MB
Info::
Fonts are 296 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 296 KB
Warning::
226 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 1.0 g CO2 per page load
4.8 MB / 2.4 MB budget
4.8 MB transferred
226 requests
1.0 g CO2 per page load
JavaScript 3.2 MiB 67%
HTML 1.0 MiB 21%
Fonts 296.2 KiB 6%
CSS 185.7 KiB 4%
Images 118.0 KiB 2%
Other 6.1 KiB 0%
Other 4.7 KiB 0%
Other 150 B 0%
Other 0 B 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over 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

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

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

D
JS Execution Cost
Action
3277ms total JS execution
FIX
3277ms total JS execution
Warning::
https://www.contentful.com/_next/static/chunks/319...: 1243ms CPU time
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-W94...: 616ms CPU time
Warning::
https://www.contentful.com/: 417ms CPU time
Warning::
Unattributable: 298ms CPU time
Info::
https://www.contentful.com/_next/static/chunks/139...: 147ms CPU time
Info::
Third-party scripts: 1337ms (41% of total)

Main Thread Breakdown

Script Evaluation 59% Other 18% Script Parsing & Compilation 8% Rendering 6% Style & Layout 5%
ScriptTotalScriptingParse/CompileParty
https://www.contentful.com/_next/static/chunks/3196-4440c14d92fe2cb9.js1243ms772ms7ms1st
https://www.googletagmanager.com/gtm.js?id=GTM-W94TVR6G616ms550ms22ms3rd
https://www.contentful.com/417ms9ms101ms1st
Unattributable298ms20ms0ms3rd
https://www.contentful.com/_next/static/chunks/1397-949ba7995b8c03e2.js147ms128ms6ms1st
https://cmp.osano.com/16BcqiRsJId123ATa/39239078-882d-46c6-9235-dcd4318a5c73/osano.js?v=prod-13012023138ms125ms7ms3rd
https://www.contentful.com/_next/static/chunks/26164011-df8e1479e3c9182b.js134ms120ms2ms1st
https://www.googletagmanager.com/gtag/js?id=G-REC62920H6&cx=c&gtm=4e6460h186ms75ms10ms3rd
https://js.qualified.com/qualified.js?token=nCX52tz3bqE643Qo85ms55ms29ms3rd
https://www.googletagmanager.com/gtag/js?id=G-SCQH3CZTQ5&cx=c&gtm=4e6460h160ms44ms15ms3rd

Showing top 10 of 11 scripts

F
JS Bundles
Action
65 scripts, 1.0 MB unused
FIX
65 scripts, 1.0 MB unused
Warning::
https://js.qualified.com/qualified.js?token=nCX52t...: 307 KB unused (84%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.contentful.com/_next/static/chunks/139...: 75 KB unused (73%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/destination?...: 70 KB unused (48%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-REC6...: 67 KB unused (37%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-SCQH...: 66 KB unused (42%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 1.0 MB
1025 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://js.qualified.com/qualified.js?token=nCX52tz3bqE643Qo370 KB307 KB (84%)✓3rd
https://www.contentful.com/_next/static/chunks/1397-949ba7995b8c03e2.js106 KB75 KB (73%)✓1st
https://www.googletagmanager.com/gtag/destination?id=AW-788978041&cx=c&gtm=4e6460h1145 KB70 KB (48%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-REC62920H6&cx=c&gtm=4e6460h1179 KB67 KB (37%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-SCQH3CZTQ5&cx=c&gtm=4e6460h1156 KB66 KB (42%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-RWVEEBSKZ3&cx=c&gtm=4e6460h1155 KB65 KB (42%)✓3rd
https://www.googletagmanager.com/gtag/destination?id=DC-14131340&cx=c&gtm=4e6460h1129 KB64 KB (50%)✓3rd
https://www.contentful.com/_next/static/chunks/3196-4440c14d92fe2cb9.js120 KB56 KB (47%)✓1st
https://www.googletagmanager.com/gtm.js?id=GTM-W94TVR6G193 KB53 KB (28%)✓3rd
https://www.contentful.com/_next/static/chunks/9571-b24846206502ac56.js91 KB49 KB (55%)✓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

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

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: private, no-cache, no-store, max-age=0, must-revalidate
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

private, no-cache, no-store, max-age=0, must-revalidate

DirectiveValueMeaning
private—Only browser cache, not CDN/proxy
no-cache—Cache but always revalidate first
no-store—Never cache this response
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
B
Third-Party Impact
52% third-party, 0 ms blocking
REVIEW
52% third-party, 0 ms blocking
Warning::
Third-party code accounts for 52% of page weight (2.5 MiB of 4.8 MiB)
Info::
Third-party blocking time is low (0 ms)
48%
52%
First-party Third-party
B
Image Optimization
27 images, 0 KB saveable
REVIEW
27 images, 0 KB saveable
Info::
All images are well-optimized
27 images 118 KB
0 oversized -0 KB
14 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

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
5 fonts (296 KB)
PASS
5 fonts (296 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

296 KB total

Render-blocking

0

of 5

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 FCP 1.3 s LCP 1.7 shttps://www.contentful.com/_next/static/media/150e0b3b650ea6d7-s.p.woff150e0b3b650ea6d7-s.p.woff https://www.contentful.com/_next/static/media/150e0b3b650ea6d7-s.p.woff — 35.7 KiB — 0 ms — font-display: swaphttps://www.contentful.com/_next/static/media/9fab8fbc3a7e1940-s.p.woff9fab8fbc3a7e1940-s.p.woff https://www.contentful.com/_next/static/media/9fab8fbc3a7e1940-s.p.woff — 35.4 KiB — 0 ms — font-display: swaphttps://www.contentful.com/_next/static/media/7195d5d0-582f-42d4-86ca-9da8dc31146e.cfdc5dbb.woff27195d5d0-582f-42d4-86ca... https://www.contentful.com/_next/static/media/7195d5d0-582f-42d4-86ca-9da8dc31146e.cfdc5dbb.woff2 — 24.4 KiB — 0 ms — font-display: swaphttps://assets.qualified.com/packs/media/Inter-Regular.f1f0c35b.woff2Inter-Regular.f1f0c35b.... https://assets.qualified.com/packs/media/Inter-Regular.f1f0c35b.woff2 — 96.9 KiB — 0 ms — font-display: swaphttps://assets.qualified.com/packs/media/Inter-SemiBold.fcb100c7.woff2Inter-SemiBold.fcb100c7... https://assets.qualified.com/packs/media/Inter-SemiBold.fcb100c7.woff2 — 103.9 KiB — 0 ms — font-display: swap
150e0b3b650ea6d7-s.p.woff woff swap
Size 36 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
9fab8fbc3a7e1940-s.p.woff woff swap
Size 35 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
7195d5d0-582f-42d4-86ca... woff2 swap
Size 24 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Inter-Regular.f1f0c35b.... woff2 swap
Size 97 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Inter-SemiBold.fcb100c7... woff2 swap
Size 104 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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 ~73 KB and ~146 ms

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
226 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
41% of JavaScript execution is third-party
First-party Third-party 1337ms · 1127KB · €23/mo
Google Tag Manager
Tag Manager
Costly
Execution 616ms
Transfer 193 KB
Unused 28%
Monthly Cost €11/mo
Unattributable
Other
Costly
Execution 298ms
Transfer 0 KB
Monthly Cost €5/mo
cmp.osano.com
Other
Optional
Execution 138ms
Transfer 74 KB
Unused 29%
Monthly Cost €2/mo
Google Tag Manager
Tag Manager
Optional
Execution 86ms
Transfer 179 KB
Unused 37%
Monthly Cost €2/mo
js.qualified.com
Other
Optional
Execution 85ms
Transfer 370 KB
Unused 84%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 60ms
Transfer 156 KB
Unused 42%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 54ms
Transfer 155 KB
Unused 42%
Monthly Cost €1/mo

These scripts may cost more than they're worth

  • Google Tag Manager adds 616ms and costs ~€11/month
  • Unattributable adds 298ms and costs ~€5/month

41% 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

Google Tag Manager takes 616ms 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

Unattributable takes 298ms 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

84% of js.qualified.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

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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