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Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
80
GRADE
B
FIX
2
REVIEW
5
PASS
5
INFO
2

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

Mobile Desktop
98
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
73
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.
85
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.

682 ms

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

1.10 s

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

2 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.

799 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.

2.41 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 5 REVIEW 2 FIX
D
Third-Party Impact
Action
83% third-party, 0 ms blocking
FIX
83% third-party, 0 ms blocking
Warning::
Third-party code accounts for 83% of page weight (1.3 MiB of 1.5 MiB)
Info::
Third-party blocking time is low (0 ms)
17%
83%
First-party Third-party
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, no-cache, must-revalidate
Info::
No ETag or Last-Modified header
Conditional requests (304 Not Modified) are not possible without validators.
Cache-Control

no-store, no-cache, must-revalidate

DirectiveValueMeaning
no-store—Never cache this response
no-cache—Cache but always revalidate first
must-revalidate—Must recheck with server after expiry
B
Page Weight Budget
1.5 MB transferred, 51 requests
REVIEW
1.5 MB transferred, 51 requests
Info::
Page weighs 4.6 MB (1.5 MB transferred)
Warning::
JavaScript is 896 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 896 KB
Info::
Fonts are 357 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 357 KB
Info::
51 HTTP requests
Info::
Estimated 0.32 g CO2 per page load
1.5 MB / 2.4 MB budget
1.5 MB transferred
51 requests
0.32 g CO2 per page load
JavaScript 896.3 KiB 57%
Fonts 356.6 KiB 23%
Images 128.8 KiB 8%
Other 99.2 KiB 6%
HTML 50.9 KiB 3%
CSS 30.2 KiB 2%
Other 4.2 KiB 0%
Other 1.9 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Approaching limit

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

B
Image Optimization
7 images, 0 KB saveable
REVIEW
7 images, 0 KB saveable
Warning::
https://cdn-assets.dzcdn.net/common/images/apple-s... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdn-assets.dzcdn.net/common/images/play-st... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
7 images 129 KB
0 oversized -0 KB
3 legacy format
2 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

B
JS Execution Cost
601ms total JS execution
REVIEW
601ms total JS execution
Info::
https://www.deezer.com/CF6YEld6/91qK8Zv/WnnBwoW/9n...: 193ms CPU time
Info::
Unattributable: 118ms CPU time
Info::
https://www.deezer.com/us/: 106ms CPU time
Info::
https://surveys-static-prd.survicate-cdn.com/widge...: 70ms CPU time
Info::
https://www.googletagmanager.com/gtm.js?id=GTM-PPQ...: 60ms CPU time
Warning::
Third-party scripts: 303ms (50% of total)

Main Thread Breakdown

Script Evaluation 59% Other 19% Script Parsing & Compilation 10% Style & Layout 9%
ScriptTotalScriptingParse/CompileParty
https://www.deezer.com/CF6YEld6/91qK8Zv/WnnBwoW/9n/E9kazL3Gwiu9Dp3Vb3/ChhnPnsWAg/TARDaxs2/DTsB193ms176ms13ms1st
Unattributable118ms18ms0ms3rd
https://www.deezer.com/us/106ms4ms1ms1st
https://surveys-static-prd.survicate-cdn.com/widget_core-28.22.7.js70ms52ms15ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-PPQNZ660ms48ms11ms3rd
https://qb3mmcu0z3.kameleoon.io/engine.js55ms44ms4ms3rd
C
JS Bundles
Action
16 scripts, 252 KB unused
REVIEW
16 scripts, 252 KB unused
Warning::
https://surveys-static-prd.survicate-cdn.com/widge...: 75 KB unused (47%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-PPQ...: 70 KB unused (39%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn-files.dzcdn.net/cache/js/app-backstage...: 68 KB unused (61%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.deezer.com/CF6YEld6/91qK8Zv/WnnBwoW/9n...: 38 KB unused (21%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 252 KB
252 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://surveys-static-prd.survicate-cdn.com/widget_core-28.22.7.js160 KB75 KB (47%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-PPQNZ6182 KB70 KB (39%)✓3rd
https://cdn-files.dzcdn.net/cache/js/app-backstage-plain-html.1de236d206f16f2e8525.js113 KB68 KB (61%)✓3rd
https://www.deezer.com/CF6YEld6/91qK8Zv/WnnBwoW/9n/E9kazL3Gwiu9Dp3Vb3/ChhnPnsWAg/TARDaxs2/DTsB179 KB38 KB (21%)✓1st
https://cdn-files.dzcdn.net/cache/js/schemaFilter.dd5daaa6c48397b27316.js1 KB—✓3rd
https://cdn-files.dzcdn.net/cache/js/bocal-en-US.4da0672db0fee6784d4d.js27 KB—✓3rd
https://cdn-assets.dzcdn.net/common/js/gdpr-appliance/index.972f32186a401ccfc6feaad320d0045dd03e93ee.js108 KB—✓3rd
https://cdn-files.dzcdn.net/cache/js/ajs-destination.9456684c162e3b4e9bd3.js3 KB—✓3rd
https://qb3mmcu0z3.kameleoon.io/engine.js43 KB—✓3rd
https://cdn.segment.com/next-integrations/actions/braze-cloud-plugins/c3dbe2dde9d1804663f0.js2 KB—✓3rd

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

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
6 fonts (357 KB)
PASS
6 fonts (357 KB)
Info::
6 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

6

357 KB total

Render-blocking

0

of 6

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 682 ms LCP 1.1 shttps://cdn-assets.dzcdn.net/common/fonts/deezer-brand/deezer-brand-bold.31cd34a97d9c1093dae0cd962ecbf6dbc3034163.woff2deezer-brand-bold.31cd3... https://cdn-assets.dzcdn.net/common/fonts/deezer-brand/deezer-brand-bold.31cd34a97d9c1093dae0cd962ecbf6dbc3034163.woff2 — 65.0 KiB — 0 ms — font-display: swaphttps://cdn-assets.dzcdn.net/common/fonts/deezer-brand/deezer-brand-extrabold.d9e833eeea6de8cf9ca90a48edf5ab1e4db5db42.woff2deezer-brand-extrabold.... https://cdn-assets.dzcdn.net/common/fonts/deezer-brand/deezer-brand-extrabold.d9e833eeea6de8cf9ca90a48edf5ab1e4db5db42.woff2 — 63.4 KiB — 0 ms — font-display: swaphttps://cdn-assets.dzcdn.net/common/fonts/inter/inter-semibold.621d67ce7463019c98c7473ab8677841ff24b1fd.woff2inter-semibold.621d67ce... https://cdn-assets.dzcdn.net/common/fonts/inter/inter-semibold.621d67ce7463019c98c7473ab8677841ff24b1fd.woff2 — 60.4 KiB — 0 ms — font-display: swaphttps://cdn-assets.dzcdn.net/common/fonts/inter/inter-medium.3f7a742daef8d40e07155f98f56b44fe7a191d94.woff2inter-medium.3f7a742dae... https://cdn-assets.dzcdn.net/common/fonts/inter/inter-medium.3f7a742daef8d40e07155f98f56b44fe7a191d94.woff2 — 52.0 KiB — 0 ms — font-display: swaphttps://cdn-assets.dzcdn.net/common/fonts/inter/inter-regular.e226d8e173551f5742af606dc1d0b184fe38ef38.woff2inter-regular.e226d8e17... https://cdn-assets.dzcdn.net/common/fonts/inter/inter-regular.e226d8e173551f5742af606dc1d0b184fe38ef38.woff2 — 55.1 KiB — 0 ms — font-display: swaphttps://cdn-assets.dzcdn.net/common/fonts/inter/inter-bold.041da318cff68d04380ea1e5d16390c5de1fa47d.woff2inter-bold.041da318cff6... https://cdn-assets.dzcdn.net/common/fonts/inter/inter-bold.041da318cff68d04380ea1e5d16390c5de1fa47d.woff2 — 60.7 KiB — 0 ms — font-display: swap
deezer-brand-bold.31cd3... woff2 swap
Size 65 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
deezer-brand-extrabold.... woff2 swap
Size 63 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
inter-semibold.621d67ce... woff2 swap
Size 60 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
inter-medium.3f7a742dae... woff2 swap
Size 52 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
inter-regular.e226d8e17... woff2 swap
Size 55 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
inter-bold.041da318cff6... woff2 swap
Size 61 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
51 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
50% of JavaScript execution is third-party
First-party Third-party 303ms · 385KB · $6/mo
Unattributable
Other
Optional
Execution 118ms
Transfer 0 KB
Monthly Cost $2/mo
surveys-static-prd.survicate-cdn.com
Other
Optional
Execution 70ms
Transfer 160 KB
Unused 47%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 60ms
Transfer 182 KB
Unused 39%
Monthly Cost $1/mo
qb3mmcu0z3.kameleoon.io
Other
Optional
Execution 55ms
Transfer 43 KB
Monthly Cost $1/mo

50% 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

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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