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https://www.decathlon.com

Performance

· 14 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
72
GRADE
C
FIX
4
REVIEW
2
PASS
6
INFO
2

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

Mobile Desktop
65
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.
81
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.

820 ms

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

1.13 s

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

538 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.

5.29 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.

9.74 s

Page Load Progression

1.3 s
2.5 s
3.8 s
5.0 s
6.3 s
7.5 s
8.8 s
10.0 s
Checks
14
6 PASS 2 REVIEW 4 FIX
F
Page Weight Budget
Action
9.5 MB transferred, 415 requests
FIX
9.5 MB transferred, 415 requests
Critical::
Page weighs 17.3 MB (9.5 MB transferred)
Warning::
Images are 4.7 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 4.7 MB
Warning::
JavaScript is 2.7 MB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 2.7 MB
Info::
Fonts are 401 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 401 KB
Warning::
415 HTTP requests — consider bundling or reducing
Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.
Info::
Estimated 2.0 g CO2 per page load
9.5 MB / 2.4 MB budget
9.5 MB transferred
415 requests
2.0 g CO2 per page load
Images 4.7 MiB 50%
JavaScript 2.7 MiB 28%
Other 1.3 MiB 14%
Fonts 400.6 KiB 4%
Other 137.2 KiB 1%
CSS 115.8 KiB 1%
HTML 95.7 KiB 1%
Other 27.0 KiB 0%
Other 9.8 KiB 0%
Other 0 B 0%
0 2.4 MB 4.9 MB
Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

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

F
JS Execution Cost
Action
7024ms total JS execution
FIX
7024ms total JS execution
Warning::
https://www.decathlon.com/: 1546ms CPU time
Warning::
Unattributable: 884ms CPU time
Warning::
https://cdn.dynamicyield.com/api/8773860/api_stati...: 611ms CPU time
Warning::
https://cdn.rebuyengine.com/onsite/js/rebuy.js?sho...: 453ms CPU time
Warning::
https://assets.gorgias.chat/build/static/js/279.58...: 312ms CPU time
Warning::
Third-party scripts: 4841ms (69% of total)

Main Thread Breakdown

Script Evaluation 47% Style & Layout 22% Other 19% Script Parsing & Compilation 7%
ScriptTotalScriptingParse/CompileParty
https://www.decathlon.com/1546ms114ms15ms1st
Unattributable884ms58ms0ms3rd
https://cdn.dynamicyield.com/api/8773860/api_static.js611ms146ms21ms3rd
https://cdn.rebuyengine.com/onsite/js/rebuy.js?shop=decathlon-usa.myshopify.com453ms251ms188ms3rd
https://assets.gorgias.chat/build/static/js/279.58c6a32e6ae4fc54.js312ms282ms12ms3rd
https://www.decathlon.com/cdn/wpm/b98d3e97aw95287a42p6e310ef5m9f58c5a0m.js296ms250ms9ms1st
https://scripts.clarity.ms/0.8.59/clarity.js283ms246ms3ms3rd
https://cdn.rebuyengine.com/onsite/js/vendors.js?id=0b003f48048b80a12360282ms140ms8ms3rd
https://cdn.rebuyengine.com/onsite/js/global.js?build=1775244697273ms209ms35ms3rd
https://cdn.rebuyengine.com/onsite/js/vendor-jquery.js?id=f643b7c5754fea9c562c215ms27ms3ms3rd

Showing top 10 of 27 scripts

F
JS Bundles
Action
211 scripts, 978 KB unused
FIX
211 scripts, 978 KB unused
Warning::
https://cdn.rebuyengine.com/onsite/js/global.js?bu...: 111 KB unused (51%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://assets.gorgias.chat/build/static/js/976.19...: 80 KB unused (68%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://assets.gorgias.chat/build/static/js/976.19...: 80 KB unused (68%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.rebuyengine.com/onsite/js/vendors.js?i...: 77 KB unused (100%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdn.dynamicyield.com/api/8773860/api_stati...: 69 KB unused (67%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 978 KB
978 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://cdn.rebuyengine.com/onsite/js/global.js?build=1775244697221 KB111 KB (51%)✓3rd
https://assets.gorgias.chat/build/static/js/976.19182ad195c0c584.js0 KB80 KB (68%)✓3rd
https://assets.gorgias.chat/build/static/js/976.19182ad195c0c584.js38 KB80 KB (68%)✓3rd
https://cdn.rebuyengine.com/onsite/js/vendors.js?id=0b003f48048b80a1236078 KB77 KB (100%)✓3rd
https://cdn.dynamicyield.com/api/8773860/api_static.js104 KB69 KB (67%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-NQJCP882N4173 KB65 KB (38%)✓3rd
https://www.googletagmanager.com/gtag/js?id=GT-MJWCF3J135 KB61 KB (45%)✓3rd
https://static.returngo.ai/master.returngo.ai/returngo.min.js?shop=decathlon-usa.myshopify.com48 KB42 KB (89%)✓3rd
https://assets.gorgias.chat/build/static/js/279.58c6a32e6ae4fc54.js93 KB41 KB (44%)✓3rd
https://static-tracking.klaviyo.com/onsite/js/build-preview/commit-f6f00cac0c842ff6b918911ae9159db809c1b007/Render.12bfc6d3a0a9b939b8c4.js52 KB37 KB (72%)✓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

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

F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.
Info::
ETag present — enables conditional (304) responses

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

B
Third-Party Impact
59% third-party, 0 ms blocking
REVIEW
59% third-party, 0 ms blocking
Warning::
Third-party code accounts for 59% of page weight (5.6 MiB of 9.5 MiB)
Info::
Third-party blocking time is low (0 ms)
41%
59%
First-party Third-party
C
Image Optimization
Action
43 images, 0 KB saveable
REVIEW
43 images, 0 KB saveable
Warning::
https://cdn.shopify.com/s/files/1/1330/6287/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdn.shopify.com/s/files/1/1752/4727/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdn.shopify.com/s/files/1/1330/6287/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdn.shopify.com/s/files/1/1752/4727/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdn.shopify.com/s/files/1/1330/6287/files/... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
43 images 4.7 MB
0 oversized -0 KB
14 legacy format
5 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

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

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
11 fonts (401 KB)
PASS
11 fonts (401 KB)
Info::
11 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

11

401 KB total

Render-blocking

0

of 11

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 500 ms 1.0 s FCP 820 ms LCP 1.1 shttps://www.decathlon.com/cdn/shop/t/334/assets/Decathlon-Brand-SemiBold.woff2?v=4101535601310826581750076865Decathlon-Brand-SemiBol... https://www.decathlon.com/cdn/shop/t/334/assets/Decathlon-Brand-SemiBold.woff2?v=4101535601310826581750076865 — 0 B — 0 ms — font-display: swaphttps://www.decathlon.com/cdn/shop/t/334/assets/Decathlon-Display-SemiBold.woff2?v=100345316253960588891750076865Decathlon-Display-SemiB... https://www.decathlon.com/cdn/shop/t/334/assets/Decathlon-Display-SemiBold.woff2?v=100345316253960588891750076865 — 0 B — 0 ms — font-display: swaphttps://www.decathlon.com/cdn/shop/t/334/assets/Decathlon-Text-Medium.woff2?v=52324173899180483681750076865Decathlon-Text-Medium.w... https://www.decathlon.com/cdn/shop/t/334/assets/Decathlon-Text-Medium.woff2?v=52324173899180483681750076865 — 0 B — 0 ms — font-display: swaphttps://www.decathlon.com/cdn/shop/t/334/assets/Decathlon-Text-SemiBold.woff2?v=2220433650020876521750076866Decathlon-Text-SemiBold... https://www.decathlon.com/cdn/shop/t/334/assets/Decathlon-Text-SemiBold.woff2?v=2220433650020876521750076866 — 0 B — 0 ms — font-display: swaphttps://www.decathlon.com/cdn/fonts/assistant/assistant_n4.9120912a469cad1cc292572851508ca49d12e768.woff2assistant_n4.9120912a46... https://www.decathlon.com/cdn/fonts/assistant/assistant_n4.9120912a469cad1cc292572851508ca49d12e768.woff2 — 12.9 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/inter/v20/UcC73FwrK3iLTeHuS_nVMrMxCp50SjIa1ZL7W0Q5nw.woff2UcC73FwrK3iLTeHuS_nVMrM... https://fonts.gstatic.com/s/inter/v20/UcC73FwrK3iLTeHuS_nVMrMxCp50SjIa1ZL7W0Q5nw.woff2 — 47.3 KiB — 0 ms — font-display: swaphttps://fonts.gstatic.com/s/inter/v20/UcC73FwrK3iLTeHuS_nVMrMxCp50SjIa1ZL7W0Q5nw.woff2UcC73FwrK3iLTeHuS_nVMrM... https://fonts.gstatic.com/s/inter/v20/UcC73FwrK3iLTeHuS_nVMrMxCp50SjIa1ZL7W0Q5nw.woff2 — 0 B — 0 ms — font-display: swaphttps://cdn.rebuyengine.com/onsite/webfonts/fa-light-300.woff2fa-light-300.woff2 https://cdn.rebuyengine.com/onsite/webfonts/fa-light-300.woff2 — 185.8 KiB — 0 ms — font-display: swaphttps://cdn.shopify.com/s/files/1/1330/6287/files/Decathlon-Display-Bold.ttf?v=1759350281Decathlon-Display-Bold.ttf https://cdn.shopify.com/s/files/1/1330/6287/files/Decathlon-Display-Bold.ttf?v=1759350281 — 51.5 KiB — 0 ms — font-display: swaphttps://cdn.shopify.com/s/files/1/1330/6287/files/Decathlon-Display-SemiBold.ttf?v=1759350281Decathlon-Display-SemiB... https://cdn.shopify.com/s/files/1/1330/6287/files/Decathlon-Display-SemiBold.ttf?v=1759350281 — 51.6 KiB — 0 ms — font-display: swaphttps://cdn.shopify.com/s/files/1/1330/6287/files/Decathlon-Display-Medium.ttf?v=1759350281Decathlon-Display-Mediu... https://cdn.shopify.com/s/files/1/1330/6287/files/Decathlon-Display-Medium.ttf?v=1759350281 — 51.5 KiB — 0 ms — font-display: swap
Decathlon-Brand-SemiBol... woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Decathlon-Display-SemiB... woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Decathlon-Text-Medium.w... woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
Decathlon-Text-SemiBold... woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
assistant_n4.9120912a46... woff2 swap
Size 13 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
UcC73FwrK3iLTeHuS_nVMrM... woff2 swap
Size 47 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
UcC73FwrK3iLTeHuS_nVMrM... woff2 swap
Size 0 KB
Load time 0 ms
Start 0 ms
Risk FOUT — text flashes from fallback to web font
fa-light-300.woff2 woff2 swap
Size 186 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
Decathlon-Display-Bold.ttf ttf swap
Size 52 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
Decathlon-Display-SemiB... ttf swap
Size 52 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
Decathlon-Display-Mediu... ttf swap
Size 52 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
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 ~139 KB and ~278 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
A+
Green Hosting
Whether the site is served from green-energy infrastructure
PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall
415 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
69% of JavaScript execution is third-party
First-party Third-party 4841ms · 1227KB · €26/mo
Unattributable
Other
Costly
Execution 884ms
Transfer 0 KB
Monthly Cost €5/mo
cdn.dynamicyield.com
Other
Costly
Execution 611ms
Transfer 104 KB
Unused 67%
Monthly Cost €3/mo
cdn.rebuyengine.com
Other
Costly
Execution 453ms
Transfer 20 KB
Monthly Cost €2/mo
assets.gorgias.chat
Other
Costly
Execution 312ms
Transfer 93 KB
Unused 44%
Monthly Cost €2/mo
Microsoft Clarity
Session Replay
Costly
Execution 283ms
Transfer 26 KB
Monthly Cost €2/mo
cdn.rebuyengine.com
Other
Costly
Execution 282ms
Transfer 78 KB
Unused 100%
Monthly Cost €2/mo
cdn.rebuyengine.com
Other
Costly
Execution 273ms
Transfer 221 KB
Unused 51%
Monthly Cost €1/mo
cdn.rebuyengine.com
Other
Costly
Execution 215ms
Transfer 32 KB
Unused 71%
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Costly
Execution 215ms
Transfer 135 KB
Unused 45%
Monthly Cost €1/mo
assets.gorgias.chat
Other
Optional
Execution 197ms
Transfer 36 KB
Monthly Cost €1/mo
st.dynamicyield.com
Other
Optional
Execution 167ms
Transfer 5 KB
Monthly Cost €1/mo
static.klaviyo.com
Other
Optional
Execution 158ms
Transfer 10 KB
Monthly Cost €1/mo
static-tracking.klaviyo.com
Other
Optional
Execution 151ms
Transfer 52 KB
Unused 72%
Monthly Cost €1/mo
static.klaviyo.com
Other
Optional
Execution 135ms
Transfer 23 KB
Monthly Cost €1/mo
cdn-app.cart-bot.net
Other
Optional
Execution 109ms
Transfer 37 KB
Monthly Cost €1/mo
static.klaviyo.com
Other
Optional
Execution 98ms
Transfer 8 KB
Monthly Cost €1/mo
Google Tag Manager
Tag Manager
Optional
Execution 69ms
Transfer 173 KB
Unused 38%
Monthly Cost €0/mo
Facebook Pixel
Advertising
Optional
Execution 62ms
Transfer 95 KB
Unused 34%
Monthly Cost €0/mo
Facebook Pixel
Advertising
Optional
Execution 59ms
Transfer 39 KB
Monthly Cost €0/mo
cdn.nfcube.com
Other
Optional
Execution 58ms
Transfer 20 KB
Monthly Cost €0/mo
cdn.nfcube.com
Other
Optional
Execution 50ms
Transfer 20 KB
Monthly Cost €0/mo

These scripts may cost more than they're worth

  • Unattributable adds 884ms and costs ~€5/month
  • cdn.dynamicyield.com adds 611ms and costs ~€3/month
  • cdn.rebuyengine.com adds 453ms and costs ~€2/month
  • assets.gorgias.chat adds 312ms and costs ~€2/month
  • Microsoft Clarity adds 283ms and costs ~€2/month
  • cdn.rebuyengine.com adds 282ms and costs ~€2/month
  • cdn.rebuyengine.com adds 273ms and costs ~€1/month
  • cdn.rebuyengine.com adds 215ms and costs ~€1/month
  • Google Tag Manager adds 215ms and costs ~€1/month

69% 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 884ms 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

cdn.dynamicyield.com takes 611ms 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

67% of cdn.dynamicyield.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

cdn.rebuyengine.com takes 453ms 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

assets.gorgias.chat takes 312ms 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

Microsoft Clarity takes 283ms 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

cdn.rebuyengine.com takes 282ms 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

100% of cdn.rebuyengine.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

cdn.rebuyengine.com takes 273ms 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

51% of cdn.rebuyengine.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

cdn.rebuyengine.com takes 215ms 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

71% of cdn.rebuyengine.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

Google Tag Manager takes 215ms 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

72% of static-tracking.klaviyo.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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