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.
9.22 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
26.76 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.
1.643
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
18.04 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.
38.06 s
Page Load Progression
FPage Weight BudgetAction6.3 MB transferred, 192 requestsFIX
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
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
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 CostAction16108ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.alaskaair.com/retaincontent/retrostack/_next/static/chunks/630fe265.45a806ad49ae5852.js | 4010ms | 3002ms | 596ms | 3rd |
| Unattributable | 2215ms | 143ms | 0ms | 3rd |
| https://www.alaskaair.com/retaincontent/retrostack/_next/static/chunks/f44aefd6.99d5d2f64ccb3b66.js | 1837ms | 1153ms | 363ms | 3rd |
| https://www.alaskaair.com/retaincontent/retrostack/_next/static/chunks/framework-2f3de63929c73f88.js | 1767ms | 1236ms | 423ms | 3rd |
| https://www.alaskaair.com/ | 1338ms | 525ms | 1ms | 3rd |
| https://cdn.optimizely.com/js/10453949094.js | 1011ms | 853ms | 72ms | 3rd |
| https://cdn.appdynamics.com/adrum/adrum-latest.js | 903ms | 578ms | 16ms | 3rd |
| https://www.alaskaair.com/retaincontent/retrostack/_next/static/chunks/1aac3323.f0cdb9870f5e1e44.js | 741ms | 459ms | 202ms | 3rd |
| 2026-03-27-atmos-homepage-modal-as-var2.js | 404ms | 310ms | 0ms | 3rd |
| https://www.alaskaair.com/_fs-ch-1T1wmsGaOgGaSxcX/clientdetection.js | 337ms | 303ms | 16ms | 3rd |
Showing top 10 of 20 scripts
FJS BundlesAction67 scripts, 960 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.alaskaair.com/retaincontent/retrostack/_next/static/chunks/630fe265.45a806ad49ae5852.js | 1218 KB | 342 KB (28%) | ✓ | 3rd |
| https://www.alaskaair.com/retaincontent/retrostack/_next/static/chunks/f44aefd6.99d5d2f64ccb3b66.js | 548 KB | 147 KB (27%) | ✓ | 3rd |
| https://www.alaskaair.com/retaincontent/retrostack/_next/static/chunks/1aac3323.f0cdb9870f5e1e44.js | 414 KB | 97 KB (23%) | ✓ | 3rd |
| https://contentcdnprodacct.blob.core.windows.net/online-chat/index.js | 112 KB | 81 KB (72%) | ✓ | 3rd |
| https://cdn.optimizely.com/js/10453949094.js | 173 KB | 69 KB (40%) | ✗ | 3rd |
| https://tags.tiqcdn.com/utag/alaska/main/prod/utag.js | 129 KB | 61 KB (49%) | ✓ | 3rd |
| https://cdn.appdynamics.com/adrum/adrum-latest.js | 150 KB | 57 KB (38%) | ✓ | 3rd |
| https://www.alaskaair.com/retaincontent/retrostack/_next/static/chunks/pages/_app-1df585c67203bc85.js | 79 KB | 33 KB (43%) | ✓ | 3rd |
| https://cdn.appdynamics.com/adrum-ext.306ca58e36f81225954b7b84627d2c85.js | 56 KB | 27 KB (49%) | ✓ | 3rd |
| https://www.alaskaair.com/_fs-ch-1T1wmsGaOgGaSxcX/clientdetection.js | 205 KB | 25 KB (12%) | ✓ | 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
FPage Weight InventoryAction192 resources · 6.3 MB · 960 KB savings availableFIX
~960.3 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 192 resources | 6.3 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization40 images, 0 KB saveableREVIEW
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 (189 KB)PASS
Web fonts
4
189 KB total
Render-blocking
0
of 4
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 Hints2 hints, 0 missing preconnectsPASS
Current Resource Hints
2 resource hints configured
A+Render-Blocking ResourcesNo render-blocking resources detectedPASS
A+Third-Party ResourcesNo third-party resources detectedPASS
Network Waterfall192 requests over 7980msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.alaskaair.com www.alaskaair.com | Other | 4010ms | 1218 KB | 28% | $75/mo | Costly |
Unattributable Unattributable | Other | 2215ms | 0 KB | — | $42/mo | Costly |
www.alaskaair.com www.alaskaair.com | Other | 1837ms | 548 KB | 27% | $34/mo | Costly |
www.alaskaair.com www.alaskaair.com | Other | 1767ms | 44 KB | — | $33/mo | Costly |
www.alaskaair.com www.alaskaair.com | Other | 1338ms | 557 KB | — | $25/mo | Costly |
Optimizely cdn.optimizely.com | A/B Testing | 1011ms | 173 KB | 40% | $19/mo | Costly |
cdn.appdynamics.com cdn.appdynamics.com | Other | 903ms | 150 KB | 38% | $17/mo | Costly |
www.alaskaair.com www.alaskaair.com | Other | 741ms | 414 KB | 23% | $14/mo | Costly |
2026-03-27-atmos-homepage-modal-as-var2.js 2026-03-27-atmos-homepage-modal-as-var2.js | Other | 404ms | 0 KB | — | $8/mo | Costly |
www.alaskaair.com www.alaskaair.com | Other | 337ms | 205 KB | 12% | $6/mo | Costly |
www.alaskaair.com www.alaskaair.com | Other | 305ms | 27 KB | — | $6/mo | Costly |
tags.tiqcdn.com tags.tiqcdn.com | Other | 285ms | 129 KB | 49% | $5/mo | Costly |
www.alaskaair.com www.alaskaair.com | Other | 227ms | 38 KB | — | $4/mo | Costly |
www.alaskaair.com www.alaskaair.com | Other | 180ms | 79 KB | 43% | $3/mo | Optional |
www.alaskaair.com www.alaskaair.com | Other | 124ms | 21 KB | — | $2/mo | Optional |
auth0.alaskaair.com auth0.alaskaair.com | Other | 110ms | 41 KB | — | $2/mo | Optional |
www.alaskaair.com www.alaskaair.com | Other | 96ms | 4 KB | — | $2/mo | Optional |
www.alaskaair.com www.alaskaair.com | Other | 85ms | 39 KB | 55% | $2/mo | Optional |
jsDelivr cdn.jsdelivr.net | CDN | 79ms | 1 KB | — | $1/mo | Optional |
www.alaskaair.com www.alaskaair.com | Other | 54ms | 7 KB | — | $1/mo | Optional |
These scripts may cost more than they're worth
- www.alaskaair.com adds 4010ms and costs ~$75/month
- Unattributable adds 2215ms and costs ~$42/month
- www.alaskaair.com adds 1837ms and costs ~$34/month
- www.alaskaair.com adds 1767ms and costs ~$33/month
- www.alaskaair.com adds 1338ms and costs ~$25/month
- Optimizely adds 1011ms and costs ~$19/month
- cdn.appdynamics.com adds 903ms and costs ~$17/month
- www.alaskaair.com adds 741ms and costs ~$14/month
- 2026-03-27-atmos-homepage-modal-as-var2.js adds 404ms and costs ~$8/month
- www.alaskaair.com adds 337ms and costs ~$6/month
- www.alaskaair.com adds 305ms and costs ~$6/month
- tags.tiqcdn.com adds 285ms and costs ~$5/month
- www.alaskaair.com adds 227ms and costs ~$4/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.alaskaair.com takes 4010ms 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 2215ms 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.alaskaair.com takes 1837ms 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.alaskaair.com takes 1767ms 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.alaskaair.com takes 1338ms 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
Optimizely takes 1011ms 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
cdn.appdynamics.com takes 903ms 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.alaskaair.com takes 741ms 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
2026-03-27-atmos-homepage-modal-as-var2.js takes 404ms 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.alaskaair.com takes 337ms 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.alaskaair.com takes 305ms 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
tags.tiqcdn.com takes 285ms 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.alaskaair.com takes 227ms 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 www.alaskaair.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