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.
9.77 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
19.85 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
2.13 s
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.212
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
16.04 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.
52.62 s
Page Load Progression
FPage Weight BudgetAction9.2 MB transferred, 130 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
Remove unused CSS rules with tools like PurgeCSS to reduce stylesheet size.
CSS bundle is large — purge unused styles (PurgeCSS, Tailwind JIT) to reduce CSS payload.
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 CostAction7232ms total JS executionFIX
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.aaos.org/ | 1394ms | 252ms | 8ms | 3rd |
| https://www.aaos.org/assets/client/dist/js/shared.bundle.min.js?v=2o4lyh3fhHcwhuJX0u4d1eDzRnN3xSFeSkioCT4i2fI | 1087ms | 657ms | 326ms | 3rd |
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604170101/pubads_impl.js?cb=31097963 | 731ms | 456ms | 83ms | 3rd |
| Unattributable | 731ms | 71ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-X356FDBRVK&cx=c>m=4e64k0 | 458ms | 407ms | 49ms | 3rd |
| https://pagead2.googlesyndication.com/pagead/managed/js/activeview/current/ufs_web_display.js | 447ms | 358ms | 38ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-TSXTNW | 354ms | 283ms | 50ms | 3rd |
| https://js.hs-analytics.net/analytics/1776894000000/20984690.js | 330ms | 300ms | 10ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-1001366057&cx=c>m=4e64k0 | 301ms | 257ms | 43ms | 3rd |
| https://www.aaos.org/bnith__n7QbTDQkVCRKy490_6f0U187iAyDMdROEZhtrRr3jEJqZkdoPX49_8u1zMfk9xuldetoVHNnErw= | 273ms | 173ms | 5ms | 3rd |
Showing top 10 of 20 scripts
FJS BundlesAction44 scripts, 2.5 MB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.aaos.org/assets/client/dist/js/shared.bundle.min.js?v=2o4lyh3fhHcwhuJX0u4d1eDzRnN3xSFeSkioCT4i2fI | 3497 KB | 2072 KB (62%) | ✓ | 3rd |
| https://securepubads.g.doubleclick.net/pagead/managed/js/gpt/m202604170101/pubads_impl.js?cb=31097963 | 187 KB | 104 KB (56%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-TSXTNW | 179 KB | 70 KB (39%) | ✓ | 3rd |
| https://www.aaos.org/assets/client/dist/js/sharethis.min.js | 119 KB | 70 KB (59%) | ✗ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-X356FDBRVK&cx=c>m=4e64k0 | 179 KB | 65 KB (37%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-1001366057&cx=c>m=4e64k0 | 146 KB | 61 KB (42%) | ✓ | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 97 KB | 32 KB (34%) | ✓ | 3rd |
| https://pagead2.googlesyndication.com/pagead/managed/js/activeview/current/ufs_web_display.js | 0 KB | 32 KB (43%) | ✓ | 3rd |
| https://pagead2.googlesyndication.com/pagead/managed/js/activeview/current/ufs_web_display.js | 73 KB | 32 KB (43%) | ✓ | 3rd |
| https://cdn.optimizely.com/js/8286478868.js | 70 KB | 30 KB (43%) | ✓ | 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 InventoryAction130 resources · 9.2 MB · 2.5 MB savings availableFIX
~2.5 MiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 130 resources | 9.2 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CImage OptimizationAction45 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
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
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
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 (67 KB)PASS
Web fonts
4
67 KB total
Render-blocking
0
of 4
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 ~19 KB and ~38 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 Waterfall130 requests over 5904msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.aaos.org www.aaos.org | Other | 1394ms | 71 KB | — | €24/mo | Costly |
www.aaos.org www.aaos.org | Other | 1087ms | 3497 KB | 62% | €19/mo | Costly |
securepubads.g.doubleclick.net securepubads.g.doubleclick.net | Other | 731ms | 187 KB | 56% | €13/mo | Costly |
Unattributable Unattributable | Other | 731ms | 0 KB | — | €13/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 458ms | 179 KB | 37% | €8/mo | Costly |
pagead2.googlesyndication.com pagead2.googlesyndication.com | Other | 447ms | 0 KB | 43% | €8/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 354ms | 179 KB | 39% | €6/mo | Costly |
HubSpot Analytics js.hs-analytics.net | Analytics | 330ms | 44 KB | — | €6/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 301ms | 146 KB | 42% | €5/mo | Costly |
www.aaos.org www.aaos.org | Other | 273ms | 65 KB | — | €5/mo | Costly |
Microsoft Clarity scripts.clarity.ms | Session Replay | 190ms | 25 KB | — | €3/mo | Optional |
Optimizely cdn.optimizely.com | A/B Testing | 181ms | 70 KB | 43% | €3/mo | Optional |
js.monitor.azure.com js.monitor.azure.com | Other | 179ms | 46 KB | — | €3/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 129ms | 97 KB | 34% | €2/mo | Optional |
cdn.feathr.co cdn.feathr.co | Other | 105ms | 42 KB | — | €2/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 79ms | 29 KB | — | €1/mo | Optional |
securepubads.g.doubleclick.net securepubads.g.doubleclick.net | Other | 75ms | 34 KB | — | €1/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 70ms | 13 KB | — | €1/mo | Optional |
Twitter/X Pixel static.ads-twitter.com | Advertising | 63ms | 13 KB | — | €1/mo | Optional |
js.hubspot.com js.hubspot.com | Other | 57ms | 28 KB | — | €1/mo | Optional |
These scripts may cost more than they're worth
- www.aaos.org adds 1394ms and costs ~€24/month
- www.aaos.org adds 1087ms and costs ~€19/month
- securepubads.g.doubleclick.net adds 731ms and costs ~€13/month
- Unattributable adds 731ms and costs ~€13/month
- Google Tag Manager adds 458ms and costs ~€8/month
- pagead2.googlesyndication.com adds 447ms and costs ~€8/month
- Google Tag Manager adds 354ms and costs ~€6/month
- HubSpot Analytics adds 330ms and costs ~€6/month
- Google Tag Manager adds 301ms and costs ~€5/month
- www.aaos.org adds 273ms and costs ~€5/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.aaos.org takes 1394ms 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.aaos.org takes 1087ms 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.aaos.org'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
securepubads.g.doubleclick.net takes 731ms 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
56% of securepubads.g.doubleclick.net'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 731ms 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 458ms 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
pagead2.googlesyndication.com takes 447ms 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 354ms 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
HubSpot Analytics takes 330ms 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 301ms 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.aaos.org takes 273ms 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