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.
1.79 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
3.74 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
42 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.005
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
2.20 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.
6.98 s
Page Load Progression
410 ms 821 ms
1.2 s
1.6 s 2.1 s 2.5 s 2.9 s
3.3 sFPage Weight BudgetAction7.4 MB transferred, 188 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
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
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 BundlesAction92 scripts, 1.4 MB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://mediahub.unl.edu/templates/iframe/js/vendor/three.min.js?v=51c855d | 593 KB | 431 KB (73%) | ✓ | 3rd |
| https://mediahub.unl.edu/templates/iframe/js/vendor/video.min.js?v=51c855d | 670 KB | 342 KB (51%) | ✓ | 3rd |
| https://larue.unl.edu/main.js?v=6.0.11 | 219 KB | 145 KB (67%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-XYGRJGQFZK&cx=c>m=4e64h1 | 178 KB | 66 KB (37%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-WKHNC39 | 172 KB | 65 KB (38%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-17881525003&cx=c>m=4e64h1 | 144 KB | 64 KB (44%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-11027044953&cx=c>m=4e64h1 | 144 KB | 61 KB (43%) | ✓ | 3rd |
| https://ucommchat.unl.edu/assets/js?for=client&version=6.0&cb=2026421 | 84 KB | 60 KB (71%) | ✗ | 3rd |
| https://mediahub.unl.edu/templates/iframe/js/vendor/jquery.min.js?v=51c855d | 88 KB | 50 KB (58%) | ✓ | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 97 KB | 33 KB (34%) | ✓ | 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 InventoryAction188 resources · 7.4 MB · 1.4 MB savings availableFIX
~1.4 MiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 188 resources | 7.4 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization30 images, 0 KB saveableREVIEW
CJS Execution CostAction1091ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://www.unl.edu/ | 260ms | 9ms | 0ms | 3rd |
| Unattributable | 225ms | 19ms | 0ms | 3rd |
| https://mediahub.unl.edu/templates/iframe/js/vendor/jquery.min.js?v=51c855d | 143ms | 117ms | 3ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-WKHNC39 | 131ms | 109ms | 18ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-XYGRJGQFZK&cx=c>m=4e64h1 | 109ms | 96ms | 11ms | 3rd |
| https://connect.facebook.net/en_US/fbevents.js | 58ms | 33ms | 25ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-11027044953&cx=c>m=4e64h1 | 57ms | 41ms | 6ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-17881525003&cx=c>m=4e64h1 | 55ms | 45ms | 10ms | 3rd |
| https://mediahub.unl.edu/templates/iframe/js/vendor/video.min.js?v=51c855d | 52ms | 35ms | 12ms | 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 Loading10 fonts (459 KB)PASS
Web fonts
10
459 KB total
Render-blocking
0
of 10
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 Waterfall188 requests over 4209msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
www.unl.edu www.unl.edu | Other | 260ms | 56 KB | — | $3/mo | Costly |
Unattributable Unattributable | Other | 225ms | 0 KB | — | $3/mo | Costly |
mediahub.unl.edu mediahub.unl.edu | Other | 143ms | 88 KB | 58% | $2/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 131ms | 172 KB | 38% | $2/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 109ms | 178 KB | 37% | $1/mo | Optional |
Facebook Pixel connect.facebook.net | Advertising | 58ms | 97 KB | 34% | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 57ms | 144 KB | 43% | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 55ms | 144 KB | 44% | $1/mo | Optional |
mediahub.unl.edu mediahub.unl.edu | Other | 52ms | 670 KB | 51% | $1/mo | Optional |
These scripts may cost more than they're worth
- www.unl.edu adds 260ms and costs ~$3/month
- Unattributable adds 225ms 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.unl.edu takes 260ms 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 225ms 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
58% of mediahub.unl.edu'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
51% of mediahub.unl.edu'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