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.
1.84 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
2.00 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
2.35 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.029
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
14.32 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.
10.04 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS Execution CostAction6152ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.bestbuy.com/kTtl3VDlj0BuKOaNiQ/Oh7JNXY1t5O5NSm9Yz/DS92/Ag/EkeEMhegkB | 1688ms | 1469ms | 109ms | 3rd |
| https://www.bestbuy.com/kTtl3VDlj0BuKOaNiQ/LN7JNXY1t5O5/D1Z6/QX/gde0diDiUPAg?v=3a2f6fb3-a0f7-37d2-7c26-c53102015435 | 1453ms | 1360ms | 51ms | 3rd |
| Unattributable | 1176ms | 359ms | 0ms | 3rd |
| https://www.bestbuy.com/kTtl3VDlj0BuKOaNiQ/LN7JNXY1t5O5/D1Z6/An/xnDRptUSUPAg?v=3a2f6fb3-a0f7-37d2-7c26-c53102015435 | 1040ms | 971ms | 46ms | 3rd |
| https://assets.bbystatic.com/analytics-dotcom/analyticsInit-f7791796aa580255fd28610903e3089e.js | 344ms | 274ms | 57ms | 3rd |
| https://www.bestbuy.com/~assets/bby/_com/cacheable-gvp-66138ea0147dd17ecdc9dc0ac1b86344.min.js | 221ms | 168ms | 50ms | 3rd |
| https://www.bestbuy.com/ | 155ms | 5ms | 2ms | 3rd |
| https://www.bestbuy.com/~assets/bby/_com/analytics-dotcom/initChildPipeline-ffee00971cdf16cacc57f870e14db909.js | 75ms | 60ms | 15ms | 3rd |
DJS BundlesAction14 scripts, 322 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.bestbuy.com/~assets/bby/_com/cacheable-gvp-66138ea0147dd17ecdc9dc0ac1b86344.min.js | 158 KB | 117 KB (74%) | ✓ | 3rd |
| https://assets.bbystatic.com/analytics-dotcom/analyticsInit-f7791796aa580255fd28610903e3089e.js | 86 KB | 47 KB (55%) | ✓ | 3rd |
| https://www.bestbuy.com/kTtl3VDlj0BuKOaNiQ/Oh7JNXY1t5O5NSm9Yz/DS92/Ag/EkeEMhegkB | 177 KB | 37 KB (21%) | ✓ | 3rd |
| https://www.bestbuy.com/kTtl3VDlj0BuKOaNiQ/Oh7JNXY1t5O5NSm9Yz/DS92/Ag/EkeEMhegkB | 177 KB | 37 KB (21%) | ✓ | 3rd |
| https://www.bestbuy.com/kTtl3VDlj0BuKOaNiQ/LN7JNXY1t5O5/D1Z6/An/xnDRptUSUPAg?v=3a2f6fb3-a0f7-37d2-7c26-c53102015435 | 161 KB | 33 KB (20%) | ✓ | 3rd |
| https://www.bestbuy.com/kTtl3VDlj0BuKOaNiQ/LN7JNXY1t5O5/D1Z6/QX/gde0diDiUPAg?v=3a2f6fb3-a0f7-37d2-7c26-c53102015435 | 152 KB | 31 KB (20%) | ✓ | 3rd |
| https://www.bestbuy.com/~assets/bby/_com/analytics-dotcom/initChildPipeline-ffee00971cdf16cacc57f870e14db909.js | 37 KB | 20 KB (56%) | ✓ | 3rd |
| https://www.bestbuy.com/~assets/bby/_intl/landing_page/js/zepto.min.js | 10 KB | — | ✓ | 3rd |
| blob:https://www.bestbuy.com/ee483ea8-a1ee-4baa-b350-b03310bfbc72 | 0 KB | — | ✓ | 3rd |
| https://www.bestbuy.com/~assets/bby/_com/legacy-66138ea0147dd17ecdc9dc0ac1b86344.min.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
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BPage Weight Budget1.0 MB transferred, 72 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
CImage OptimizationAction4 images, 0 KB saveableREVIEW
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
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
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
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
BPage Weight Inventory72 resources · 1.0 MB · 322 KB savings availableREVIEW
~322.0 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 72 resources | 1.0 MiB | ||||||
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 Loading3 fonts (64 KB)PASS
Web fonts
3
64 KB total
Render-blocking
0
of 3
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+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall72 requests over 28559msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.bestbuy.com www.bestbuy.com | Other | 1688ms | 1 KB | 21% | $22/mo | Costly |
www.bestbuy.com www.bestbuy.com | Other | 1453ms | 152 KB | 20% | $19/mo | Costly |
Unattributable Unattributable | Other | 1176ms | 0 KB | — | $16/mo | Costly |
www.bestbuy.com www.bestbuy.com | Other | 1040ms | 161 KB | 20% | $14/mo | Costly |
assets.bbystatic.com assets.bbystatic.com | Other | 344ms | 86 KB | 55% | $5/mo | Costly |
www.bestbuy.com www.bestbuy.com | Other | 221ms | 158 KB | 74% | $3/mo | Costly |
www.bestbuy.com www.bestbuy.com | Other | 155ms | 4 KB | — | $2/mo | Optional |
www.bestbuy.com www.bestbuy.com | Other | 75ms | 37 KB | 56% | $1/mo | Optional |
These scripts may cost more than they're worth
- www.bestbuy.com adds 1688ms and costs ~$22/month
- www.bestbuy.com adds 1453ms and costs ~$19/month
- Unattributable adds 1176ms and costs ~$16/month
- www.bestbuy.com adds 1040ms and costs ~$14/month
- assets.bbystatic.com adds 344ms and costs ~$5/month
- www.bestbuy.com adds 221ms 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.bestbuy.com takes 1688ms 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.bestbuy.com takes 1453ms 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 1176ms 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.bestbuy.com takes 1040ms 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
assets.bbystatic.com takes 344ms 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
55% of assets.bbystatic.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
www.bestbuy.com takes 221ms 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 www.bestbuy.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
56% of www.bestbuy.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