Performance
· 17 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.
2.49 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
5.17 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
1.18 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.001
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
5.27 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.
13.07 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction6281ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.threadless.com/ | 2767ms | 62ms | 3ms | 3rd |
| Unattributable | 604ms | 81ms | 0ms | 3rd |
| https://www.threadless.com/wrjj/ | 502ms | 412ms | 72ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-WHSLYJRBDP&cx=c>m=4e64k0 | 502ms | 413ms | 77ms | 3rd |
| https://www.threadless.com/cdn-cgi/scripts/7d0fa10a/cloudflare-static/rocket-loader.min.js | 387ms | 307ms | 15ms | 3rd |
| https://www.threadless.com/cdn-cgi/challenge-platform/scripts/jsd/main.js | 386ms | 367ms | 6ms | 3rd |
| https://connect.facebook.net/signals/config/571177840158185?v=2.9.303&r=stable&domain=www.threadless.com&hme=97937018cefade17726f0472876fc101316b2ce9008a35a6a5a7977d7436151a&ex_m=104%2C205%2C154%2C22%2C72%2C73%2C145%2C68%2C67%2C11%2C162%2C90%2C16%2C138%2C127%2C39%2C75%2C78%2C134%2C159%2C164%2C8%2C4%2C5%2C7%2C6%2C3%2C91%2C101%2C165%2C170%2C219%2C62%2C186%2C187%2C55%2C276%2C30%2C74%2C231%2C230%2C229%2C23%2C33%2C103%2C61%2C10%2C63%2C97%2C98%2C99%2C105%2C130%2C31%2C29%2C132%2C133%2C129%2C128%2C155%2C76%2C158%2C156%2C157%2C50%2C60%2C123%2C15%2C161%2C45%2C263%2C264%2C262%2C26%2C27%2C28%2C48%2C146%2C77%2C112%2C18%2C20%2C44%2C40%2C42%2C41%2C83%2C92%2C96%2C110%2C144%2C147%2C46%2C111%2C24%2C21%2C119%2C69%2C36%2C149%2C148%2C150%2C141%2C139%2C25%2C35%2C59%2C109%2C160%2C70%2C17%2C152%2C114%2C81%2C66%2C19%2C85%2C86%2C116%2C84%2C136%2C135%2C34%2C278%2C293%2C212%2C201%2C202%2C200%2C296%2C288%2C52%2C213%2C107%2C131%2C80%2C121%2C54%2C47%2C49%2C113%2C120%2C126%2C58%2C64%2C151%2C115%2C37%2C32%2C53%2C56%2C100%2C163%2C1%2C124%2C14%2C122%2C12%2C2%2C57%2C93%2C65%2C118%2C89%2C88%2C166%2C167%2C94%2C95%2C9%2C125%2C102%2C51%2C142%2C87%2C79%2C71%2C117%2C106%2C43%2C143%2C0%2C82%2C137%2C140%2C153%2C38%2C108%2C13%2C168 | 384ms | 322ms | 61ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-MCSQ99 | 274ms | 206ms | 64ms | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 210ms | 140ms | 68ms | 3rd |
| https://cdn-media.threadless.com/static_11/js/base.314582382db5.js | 84ms | 56ms | 13ms | 3rd |
Showing top 10 of 13 scripts
DPage Weight InventoryAction69 resources · 1.5 MB · 289 KB savings availableFIX
~288.6 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 69 resources | 1.5 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BPage Weight Budget1.5 MB transferred, 69 requestsREVIEW
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
Subset fonts to include only used characters, or switch to system font stacks.
Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).
Source: web.dev font loading
BImage Optimization25 images, 0 KB saveableREVIEW
Set explicit width and height to prevent CLS.
Performance issues directly impact user engagement and conversion rates.
CJS BundlesAction19 scripts, 289 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-WHSLYJRBDP&cx=c>m=4e64k0 | 178 KB | 69 KB (39%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-MCSQ99 | 146 KB | 66 KB (45%) | ✓ | 3rd |
| https://www.threadless.com/wrjj/ | 175 KB | 63 KB (36%) | ✓ | 3rd |
| https://connect.facebook.net/signals/config/571177840158185?v=2.9.303&r=stable&domain=www.threadless.com&hme=97937018cefade17726f0472876fc101316b2ce9008a35a6a5a7977d7436151a&ex_m=104%2C205%2C154%2C22%2C72%2C73%2C145%2C68%2C67%2C11%2C162%2C90%2C16%2C138%2C127%2C39%2C75%2C78%2C134%2C159%2C164%2C8%2C4%2C5%2C7%2C6%2C3%2C91%2C101%2C165%2C170%2C219%2C62%2C186%2C187%2C55%2C276%2C30%2C74%2C231%2C230%2C229%2C23%2C33%2C103%2C61%2C10%2C63%2C97%2C98%2C99%2C105%2C130%2C31%2C29%2C132%2C133%2C129%2C128%2C155%2C76%2C158%2C156%2C157%2C50%2C60%2C123%2C15%2C161%2C45%2C263%2C264%2C262%2C26%2C27%2C28%2C48%2C146%2C77%2C112%2C18%2C20%2C44%2C40%2C42%2C41%2C83%2C92%2C96%2C110%2C144%2C147%2C46%2C111%2C24%2C21%2C119%2C69%2C36%2C149%2C148%2C150%2C141%2C139%2C25%2C35%2C59%2C109%2C160%2C70%2C17%2C152%2C114%2C81%2C66%2C19%2C85%2C86%2C116%2C84%2C136%2C135%2C34%2C278%2C293%2C212%2C201%2C202%2C200%2C296%2C288%2C52%2C213%2C107%2C131%2C80%2C121%2C54%2C47%2C49%2C113%2C120%2C126%2C58%2C64%2C151%2C115%2C37%2C32%2C53%2C56%2C100%2C163%2C1%2C124%2C14%2C122%2C12%2C2%2C57%2C93%2C65%2C118%2C89%2C88%2C166%2C167%2C94%2C95%2C9%2C125%2C102%2C51%2C142%2C87%2C79%2C71%2C117%2C106%2C43%2C143%2C0%2C82%2C137%2C140%2C153%2C38%2C108%2C13%2C168 | 127 KB | 36 KB (29%) | ✓ | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 97 KB | 34 KB (35%) | ✓ | 3rd |
| https://cdn-media.threadless.com/static_11/js/base.314582382db5.js | 29 KB | 21 KB (74%) | ✓ | 3rd |
| https://cdn-media.threadless.com/static_11/platform_likes/_SaveFollow.2d2823ea59ac.js | 2 KB | — | ✓ | 3rd |
| https://cdn-media.threadless.com/static_11/js/base_anon.1ef7058cc16d.js | 3 KB | — | ✓ | 3rd |
| https://googleads.g.doubleclick.net/pagead/viewthroughconversion/868006678/?random=1776890829807&cv=11&fst=1776890829807&bg=ffffff&guid=ON&async=1&en=gtag.config>m=45g92e64k0v9164638589za204zd9164638589xec&gcd=13l3l3l3l1l1&dma=0&tag_exp=0~115938465~115938468~117266401~117512543&u_w=412&u_h=823&url=https%3A%2F%2Fwww.threadless.com%2F&rcb=13&frm=0&tiba=Up%20to%2035%25%20Off%20Everything%20at%20Threadless&did=dYzg1YT&gdid=dYzg1YT.dNzQzZD&hn=www.googleadservices.com&npa=0&pscdl=noapi&auid=330384559.1776890830&uaa=&uab=64&uafvl=Not-A.Brand%3B24.0.0.0%7CChromium%3B146.0.7680.164&uamb=1&uam=moto%20g%20power%20(2022)&uap=Android&uapv=11.0&uaw=0&data=event%3Dgtag.config&gap.gtb=1&rfmt=3&fmt=4 | 2 KB | — | ✓ | 3rd |
| https://cdn-media.threadless.com/static_11/js/payment_buttons.1df930d69f19.js | 7 KB | — | ✓ | 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
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
A+Font Loading4 fonts (349 KB)PASS
Web fonts
4
349 KB total
Render-blocking
0
of 4
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- 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 ~136 KB and ~272 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall69 requests over 3534msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.threadless.com www.threadless.com | Other | 2767ms | 26 KB | — | $37/mo | Costly |
Unattributable Unattributable | Other | 604ms | 0 KB | — | $8/mo | Costly |
www.threadless.com www.threadless.com | Other | 502ms | 175 KB | 36% | $7/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 502ms | 178 KB | 39% | $7/mo | Costly |
www.threadless.com www.threadless.com | Other | 387ms | 4 KB | — | $5/mo | Costly |
www.threadless.com www.threadless.com | Other | 386ms | 0 KB | — | $5/mo | Costly |
Facebook Pixel connect.facebook.net | Advertising | 384ms | 127 KB | 29% | $5/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 274ms | 146 KB | 45% | $4/mo | Costly |
Facebook Pixel connect.facebook.net | Advertising | 210ms | 97 KB | 35% | $3/mo | Costly |
cdn-media.threadless.com cdn-media.threadless.com | Other | 84ms | 29 KB | 74% | $1/mo | Optional |
static.cloudflareinsights.com static.cloudflareinsights.com | Other | 78ms | 11 KB | — | $1/mo | Optional |
cdnjs cdnjs.cloudflare.com | CDN | 53ms | 0 KB | — | $1/mo | Optional |
cdnjs cdnjs.cloudflare.com | CDN | 51ms | 4 KB | — | $1/mo | Optional |
These scripts may cost more than they're worth
- www.threadless.com adds 2767ms and costs ~$37/month
- Unattributable adds 604ms and costs ~$8/month
- www.threadless.com adds 502ms and costs ~$7/month
- Google Tag Manager adds 502ms and costs ~$7/month
- www.threadless.com adds 387ms and costs ~$5/month
- www.threadless.com adds 386ms and costs ~$5/month
- Facebook Pixel adds 384ms and costs ~$5/month
- Google Tag Manager adds 274ms and costs ~$4/month
- Facebook Pixel adds 210ms and costs ~$3/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.threadless.com takes 2767ms 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
Unattributable takes 604ms 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.threadless.com takes 502ms 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 502ms 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.threadless.com takes 387ms 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.threadless.com takes 386ms 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
Facebook Pixel takes 384ms 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 274ms 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
Facebook Pixel takes 210ms 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
74% of cdn-media.threadless.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