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.
1.28 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
3.08 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
0 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.010
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
2.73 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.
3.09 s
Page Load Progression
FPage Weight BudgetAction11.5 MB transferred, 116 requestsFIX
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
Subset fonts to include only used characters, or switch to system font stacks.
Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).
Source: web.dev font loading
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
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
DPage Weight InventoryAction116 resources · 11.5 MB · 169 KB savings availableFIX
~169.3 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 116 resources | 11.5 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BThird-Party Impact52% third-party, 0 ms blockingREVIEW
CImage OptimizationAction37 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
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
BJS Execution Cost735ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.virginia.edu/ | 262ms | 14ms | 1ms | 1st |
| Unattributable | 156ms | 5ms | 0ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-58VK8DX | 108ms | 93ms | 10ms | 3rd |
| https://script.crazyegg.com/pages/versioned/common-scripts/4ce8c7df8d425cc50464576824ed91eb.js | 82ms | 70ms | 3ms | 3rd |
| https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js | 74ms | 44ms | 2ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-J44315NZPS&cx=c>m=4e64h1 | 52ms | 42ms | 9ms | 3rd |
CJS BundlesAction23 scripts, 169 KB unusedREVIEW
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-J44315NZPS&cx=c>m=4e64h1 | 170 KB | 68 KB (40%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-58VK8DX | 150 KB | 48 KB (32%) | ✓ | 3rd |
| https://script.crazyegg.com/pages/versioned/common-scripts/4ce8c7df8d425cc50464576824ed91eb.js | 55 KB | 27 KB (50%) | ✓ | 3rd |
| https://customer.cludo.com/scripts/bundles/search-script.min.js | 51 KB | 26 KB (52%) | ✓ | 3rd |
| https://cdn.jsdelivr.net/npm/slick-carousel@1.8.1/slick/slick.min.js | 11 KB | — | ✓ | 3rd |
| https://script.crazyegg.com/pages/scripts/0090/5137.js | 3 KB | — | ✓ | 3rd |
| https://www.virginia.edu/assets/js/calendar-feed.js | 1 KB | — | ✓ | 1st |
| https://www.virginia.edu/assets/js/search_functions_v2.js?1 | 2 KB | — | ✓ | 1st |
| https://cdn.parsely.com/keys/virginia.edu/p.js | 19 KB | — | ✓ | 3rd |
| https://www.virginia.edu/assets/js/mobile-submenu-toggle.js | 1 KB | — | ✓ | 1st |
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
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 Loading30 fonts (890 KB)PASS
Web fonts
30
890 KB total
Render-blocking
0
of 30
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
- 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 ~77 KB and ~154 ms
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
Network Waterfall116 requests over 3342msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 156ms | 0 KB | — | $2/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 108ms | 150 KB | 32% | $1/mo | Optional |
script.crazyegg.com script.crazyegg.com | Other | 82ms | 55 KB | 50% | $1/mo | Optional |
ajax.googleapis.com ajax.googleapis.com | Other | 74ms | 30 KB | — | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 52ms | 170 KB | 40% | $1/mo | Optional |
64% of JavaScript execution time comes from third-party scripts.
Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.
Learn more ▾ ▴
Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.
Source: web.dev / HTTP Archive Web Almanac