Performance
· 22 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.
1.38 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
1.61 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
16 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.003
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.38 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.
2.05 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DPage Weight InventoryAction85 resources · 1.3 MB · 294 KB savings availableFIX
~293.6 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 85 resources | 1.3 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BPage Weight Budget1.3 MB transferred, 85 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
BJS Execution Cost743ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://asset.zcache.com/bld/z.3/desktop/vendor.f2d3132478bb08.js | 192ms | 174ms | 0ms | 3rd |
| Unattributable | 186ms | 72ms | 0ms | 3rd |
| https://www.zazzle.com/ | 141ms | 5ms | 8ms | 3rd |
| https://www.zazzle.com/cgtw/X75t_m90HdNuaQI51oK8cqAbrGP79AeZpaCIBu9S4t-9ZnT1eHQujFzU6g | 94ms | 74ms | 17ms | 3rd |
| https://www.zazzle.com/cgtw/?id=GTM-MLV372Q>m_auth=PK96U0sSRa3-sRYTKoYtBQ>m_preview=env-57>m_cookies_win=x | 73ms | 61ms | 11ms | 3rd |
| https://www.zazzle.com/_fs-ch-1T1wmsGaOgGaSxcX/assets/botdefence.js | 56ms | 50ms | 5ms | 3rd |
CJS BundlesAction32 scripts, 294 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.zazzle.com/cgtw/X75t_m90HdNuaQI51oK8cqAbrGP79AeZpaCIBu9S4t-9ZnT1eHQujFzU6g | 182 KB | 73 KB (40%) | ✓ | 3rd |
| https://www.zazzle.com/cgtw/?id=GTM-MLV372Q>m_auth=PK96U0sSRa3-sRYTKoYtBQ>m_preview=env-57>m_cookies_win=x | 155 KB | 61 KB (39%) | ✓ | 3rd |
| https://asset.zcache.com/bld/z.3/desktop/purchase.dc3e87f7e4d382.js | 106 KB | 55 KB (60%) | ✓ | 3rd |
| https://asset.zcache.com/bld/z.3/desktop/vendor.f2d3132478bb08.js | 114 KB | 42 KB (37%) | ✓ | 3rd |
| https://www.zazzle.com/_fs-ch-1T1wmsGaOgGaSxcX/assets/botdefence.js | 217 KB | 33 KB (15%) | ✓ | 3rd |
| https://asset.zcache.com/bld/z.3/desktop/header-Header2021.6b28e516fde714.js | 46 KB | 31 KB (67%) | ✓ | 3rd |
| https://asset.zcache.com/bld/z.3/desktop/CCAIChat-CcaiHeadlessRootWrapper.3d5fc42e6eee54.js | 1 KB | — | ✓ | 3rd |
| https://asset.zcache.com/bld/z.3/desktop/5.b257baffb1be49.js | 5 KB | — | ✓ | 3rd |
| https://asset.zcache.com/bld/z.3/desktop/23.65c34d0220496f.js | 4 KB | — | ✓ | 3rd |
| https://asset.zcache.com/bld/z.3/desktop/32.b498ca635212c4.js | 8 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
BHTTP/3 (QUIC)HTTP/3 not advertisedREVIEW
CCompression AlgorithmActionMain response served uncompressedREVIEW
BMain HTML Cache-ControlNo Cache-Control header on main HTML responseREVIEW
BServer-Timing ObservabilityNo Server-Timing header foundREVIEW
CGreen HostingActionWhether the site is served from green-energy infrastructureREVIEW
Green Hosting
No green hosting detected
A+Text CompressionAll text resources are compressedPASS
AImage Optimization13 images, 0 KB saveablePASS
Set explicit width and height to prevent CLS.
Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.
Source: web.dev / Core Web Vitals
A+Font Loading7 fonts (151 KB)PASS
Web fonts
7
151 KB total
Render-blocking
0
of 7
Dominant font-display
swap
Most common across fonts
Font loading timeline
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 CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+LCP Image PreloadLCP preload audit not availablePASS
A+Server Response Intelligence1 server-response signal(s) detectedPASS
Network Waterfall85 requests over 1776msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
asset.zcache.com asset.zcache.com | Other | 192ms | 114 KB | 37% | $3/mo | Optional |
Unattributable Unattributable | Other | 186ms | 0 KB | — | $2/mo | Optional |
www.zazzle.com www.zazzle.com | Other | 141ms | 60 KB | — | $2/mo | Optional |
www.zazzle.com www.zazzle.com | Other | 94ms | 182 KB | 40% | $1/mo | Optional |
www.zazzle.com www.zazzle.com | Other | 73ms | 155 KB | 39% | $1/mo | Optional |
www.zazzle.com www.zazzle.com | Other | 56ms | 217 KB | 15% | $1/mo | Optional |
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
Image Optimization2 images, 0 KB total, 0 KB wastedINFO
Image Optimization Audit
Total Images
2
Total Size
0 KB
Oversized
2