Performance
· 15 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.
1.40 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
3.85 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
195 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
1.014
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
2.86 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.
4.10 s
Page Load Progression
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
DJS BundlesAction21 scripts, 321 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-4JTET9KDVF&cx=c>m=4e64h1 | 173 KB | 68 KB (39%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-MXGB7Z | 178 KB | 65 KB (37%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-G3S3K4BJ32&cx=c>m=4e64h1 | 172 KB | 64 KB (37%) | ✓ | 3rd |
| https://www.google.com/cse/static/element/b33cba5881f68fbf/cse_element__en.js?usqp=CAI%3D | 99 KB | 48 KB (49%) | ✓ | 3rd |
| https://cse.google.com/adsense/search/async-ads.js | 44 KB | 32 KB (73%) | ✓ | 3rd |
| https://www.uvm.edu/d10-files/js/js_XVt3l2VOIt6LRj8LCDE6oLgxR5OyxwmqXurzxlhjLcI.js?scope=footer&delta=2&language=en&theme=uvm_theme&include=eJxtjkEOAiEMRS_EQMYLkQoVq4USKKNze0mchRo3ff2vi36IUQXK7uBY7KVJUROkoYttVGCrMsIVNyzaF8U-j_UUmKo7aBPLGdjg8EHkTjiRKxOUgO6fNEkkMXqF5NIcv9nCDZ7fMptOig-K6IGxqaNCasaWvV4xzzeRVBrBuu4f9l1s6bozlfQCTaNbUg | 34 KB | 24 KB (71%) | ✓ | 3rd |
| https://static.addtoany.com/menu/modules/core.ydpp7jcu.js | 26 KB | 21 KB (82%) | ✓ | 3rd |
| https://www.uvm.edu/modules/contrib/google_tag/js/gtag.js?tdsqgj | 1 KB | — | ✓ | 3rd |
| https://static.addtoany.com/menu/page.js | 2 KB | — | ✓ | 3rd |
| https://www.uvm.edu/d10-files/js/js_hIpaI8qzaNV0eUMEsd4ymUIqFlC_hyZR6bOSOqrHD6A.js?scope=footer&delta=0&language=en&theme=uvm_theme&include=eJxtjkEOAiEMRS_EQMYLkQoVq4USKKNze0mchRo3ff2vi36IUQXK7uBY7KVJUROkoYttVGCrMsIVNyzaF8U-j_UUmKo7aBPLGdjg8EHkTjiRKxOUgO6fNEkkMXqF5NIcv9nCDZ7fMptOig-K6IGxqaNCasaWvV4xzzeRVBrBuu4f9l1s6bozlfQCTaNbUg | 40 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
DPage Weight InventoryAction69 resources · 2.0 MB · 321 KB savings availableFIX
~321.0 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 69 resources | 2.0 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
CPage Weight BudgetAction2.0 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
CImage OptimizationAction21 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
CJS Execution CostAction1205ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.uvm.edu/d10-files/js/js_hIpaI8qzaNV0eUMEsd4ymUIqFlC_hyZR6bOSOqrHD6A.js?scope=footer&delta=0&language=en&theme=uvm_theme&include=eJxtjkEOAiEMRS_EQMYLkQoVq4USKKNze0mchRo3ff2vi36IUQXK7uBY7KVJUROkoYttVGCrMsIVNyzaF8U-j_UUmKo7aBPLGdjg8EHkTjiRKxOUgO6fNEkkMXqF5NIcv9nCDZ7fMptOig-K6IGxqaNCasaWvV4xzzeRVBrBuu4f9l1s6bozlfQCTaNbUg | 414ms | 71ms | 3ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-MXGB7Z | 216ms | 140ms | 69ms | 3rd |
| Unattributable | 144ms | 4ms | 0ms | 3rd |
| https://www.uvm.edu/ | 136ms | 5ms | 1ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-G3S3K4BJ32&cx=c>m=4e64h1 | 107ms | 88ms | 17ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-4JTET9KDVF&cx=c>m=4e64h1 | 99ms | 79ms | 19ms | 3rd |
| https://scripts.clarity.ms/0.8.59/clarity.js | 89ms | 78ms | 3ms | 3rd |
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 Loading2 fonts (58 KB)PASS
Web fonts
2
58 KB total
Render-blocking
0
of 2
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
Network Waterfall69 requests over 5166msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.uvm.edu www.uvm.edu | Other | 414ms | 40 KB | — | $6/mo | Costly |
Google Tag Manager www.googletagmanager.com | Tag Manager | 216ms | 178 KB | 37% | $3/mo | Costly |
Unattributable Unattributable | Other | 144ms | 0 KB | — | $2/mo | Optional |
www.uvm.edu www.uvm.edu | Other | 136ms | 39 KB | — | $2/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 107ms | 172 KB | 37% | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 99ms | 173 KB | 39% | $1/mo | Optional |
Microsoft Clarity scripts.clarity.ms | Session Replay | 89ms | 26 KB | — | $1/mo | Optional |
These scripts may cost more than they're worth
- www.uvm.edu adds 414ms and costs ~$6/month
- Google Tag Manager adds 216ms 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.uvm.edu takes 414ms 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 216ms 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