Performance
· 16 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.
11.60 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
30.71 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
5.08 s
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.
21.35 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.
48.48 s
Page Load Progression
FPage Weight BudgetAction53.9 MB transferred, 174 requestsFIX
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
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.
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.
High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.
Source: web.dev
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction27394ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.gymshark.com/ | 8821ms | 30ms | 4ms | 3rd |
| https://www.gymshark.com/_next/static/chunks/framework-37ae32f58c38fef9.js | 5046ms | 4054ms | 18ms | 3rd |
| https://www.gymshark.com/_next/static/chunks/pages/_app-77dacc2b8f5bc3cc.js | 3193ms | 2106ms | 382ms | 3rd |
| Unattributable | 3127ms | 105ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-WQXVFFG>m_auth=>m_preview=>m_cookies_win=x | 1746ms | 1586ms | 94ms | 3rd |
| https://10ef4229c7d0.edge.sdk.awswaf.com/10ef4229c7d0/f2cb19c6a7d6/challenge.js | 1321ms | 1094ms | 147ms | 3rd |
| https://js.intercomcdn.com/vendor-modern.df860bed.js | 1130ms | 884ms | 49ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-PQJ0N2K1QF&cx=c>m=4e6461 | 1075ms | 857ms | 55ms | 3rd |
| https://www.googletagmanager.com/gtag/destination?id=AW-823557903&cx=c>m=4e6461 | 318ms | 255ms | 61ms | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 275ms | 220ms | 54ms | 3rd |
Showing top 10 of 21 scripts
FJS BundlesAction31 scripts, 1.8 MB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.gymshark.com/_next/static/chunks/pages/_app-77dacc2b8f5bc3cc.js | 1065 KB | 660 KB (62%) | ✓ | 3rd |
| https://10ef4229c7d0.edge.sdk.awswaf.com/10ef4229c7d0/f2cb19c6a7d6/challenge.js | 501 KB | 261 KB (52%) | ✓ | 3rd |
| https://js.intercomcdn.com/frame-modern.c43524e8.js | 192 KB | 122 KB (64%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/destination?id=G-PQJ0N2K1QF&cx=c>m=4e6461 | 173 KB | 112 KB (65%) | ✓ | 3rd |
| https://js.intercomcdn.com/vendor-modern.df860bed.js | 144 KB | 86 KB (60%) | ✓ | 3rd |
| https://jssdkcdns.mparticle.com/js/v2/eu1-ebd2cad076757c498ce604d818b0d8ae/mparticle.js?env=0&plan_id=gymshark_data_plan_shop | 132 KB | 81 KB (61%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/destination?id=AW-933026149&cx=c>m=4e6461 | 133 KB | 68 KB (51%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/destination?id=AW-823557903&cx=c>m=4e6461 | 133 KB | 67 KB (50%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-WQXVFFG>m_auth=>m_preview=>m_cookies_win=x | 210 KB | 64 KB (31%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-PQJ0N2K1QF&cx=c>m=4e6461 | 173 KB | 61 KB (35%) | ✓ | 3rd |
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
DHTTP CachingActionno-store (uncacheable)FIX
private, no-store
| Directive | Value | Meaning |
|---|---|---|
| private | — | Only browser cache, not CDN/proxy |
| no-store | — | Never cache this response |
BImage Optimization91 images, 0 KB saveableREVIEW
A+Text CompressionAll text resources are compressedPASS
A+Font Loading11 fonts (117 KB)PASS
Web fonts
11
117 KB total
Render-blocking
0
of 11
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Convert to woff2 for ~30% smaller file size
- Convert to woff2 for ~30% smaller file size
- 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 ~24 KB and ~48 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource Hints8 hints, 0 missing preconnectsPASS
Current Resource Hints
8 resource hints configured
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
Network Waterfall174 requests over 0msINFO
Performance analysis not available for this result.
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.gymshark.com www.gymshark.com | Other | 8821ms | 83 KB | — | $50/mo | Costly |
www.gymshark.com www.gymshark.com | Other | 5046ms | 44 KB | — | $29/mo | Costly |
www.gymshark.com www.gymshark.com | Other | 3193ms | 1065 KB | 62% | $18/mo | Costly |
Unattributable Unattributable | Other | 3127ms | 0 KB | — | $18/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 1746ms | 210 KB | 31% | $10/mo | Costly |
10ef4229c7d0.edge.sdk.awswaf.com 10ef4229c7d0.edge.sdk.awswaf.com | Other | 1321ms | 501 KB | 52% | $8/mo | Costly |
js.intercomcdn.com js.intercomcdn.com | Other | 1130ms | 144 KB | 60% | $6/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 1075ms | 173 KB | 35% | $6/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 318ms | 133 KB | 50% | $2/mo | Costly |
Facebook Pixel connect.facebook.net | Advertising | 275ms | 95 KB | 45% | $2/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 223ms | 133 KB | 51% | $1/mo | Costly |
OneTrust cdn.cookielaw.org | Consent | 165ms | 80 KB | 60% | $1/mo | Essential |
www.gymshark.com www.gymshark.com | Other | 163ms | 40 KB | — | $1/mo | Optional |
jssdkcdns.mparticle.com jssdkcdns.mparticle.com | Other | 154ms | 132 KB | 61% | $1/mo | Optional |
web-assets.stylitics.com web-assets.stylitics.com | Other | 145ms | 59 KB | 63% | $1/mo | Optional |
Intercom Widget widget.intercom.io | Chat | 101ms | 4 KB | — | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 95ms | 173 KB | 65% | $1/mo | Optional |
www.gymshark.com www.gymshark.com | Other | 95ms | 114 KB | — | $1/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 73ms | 37 KB | — | $0/mo | Optional |
js.intercomcdn.com js.intercomcdn.com | Other | 70ms | 192 KB | 64% | $0/mo | Optional |
OneTrust cdn.cookielaw.org | Consent | 59ms | 9 KB | — | $0/mo | Essential |
These scripts may cost more than they're worth
- www.gymshark.com adds 8821ms and costs ~$50/month
- www.gymshark.com adds 5046ms and costs ~$29/month
- www.gymshark.com adds 3193ms and costs ~$18/month
- Unattributable adds 3127ms and costs ~$18/month
- Google Tag Manager adds 1746ms and costs ~$10/month
- 10ef4229c7d0.edge.sdk.awswaf.com adds 1321ms and costs ~$8/month
- js.intercomcdn.com adds 1130ms and costs ~$6/month
- Google Tag Manager adds 1075ms and costs ~$6/month
- Google Tag Manager adds 318ms and costs ~$2/month
- Facebook Pixel adds 275ms and costs ~$2/month
- Google Tag Manager adds 223ms and costs ~$1/month
100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.
When third-party JS execution time exceeds your own, performance gains from frontend work are capped by code you don't own.
Learn more ▾ ▴
Every millisecond of third-party JS competes with your own for main-thread time. If their share is bigger than yours, optimization on your code base barely moves the needle. Audit, defer, or remove third-parties before further frontend optimization. Use Lighthouse's third-party audit to identify the worst offenders.
Source: web.dev
www.gymshark.com takes 8821ms 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
www.gymshark.com takes 5046ms 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
www.gymshark.com takes 3193ms 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
62% of www.gymshark.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
Unattributable takes 3127ms 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 1746ms 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
10ef4229c7d0.edge.sdk.awswaf.com takes 1321ms 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
52% of 10ef4229c7d0.edge.sdk.awswaf.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
js.intercomcdn.com takes 1130ms 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
60% of js.intercomcdn.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
Google Tag Manager takes 1075ms 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 318ms 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
50% of Google Tag Manager's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
Facebook Pixel takes 275ms 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 223ms 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
51% of Google Tag Manager's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
60% of OneTrust's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
61% of jssdkcdns.mparticle.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
63% of web-assets.stylitics.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
65% of Google Tag Manager's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev
64% of js.intercomcdn.com's code is unused. The script may be loading features you don't use.
Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.
Source: web.dev