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.
1.16 s
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
2.13 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
50 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.000
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
3.76 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.
4.54 s
Page Load Progression
FPage Weight BudgetAction5.4 MB transferred, 80 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
DThird-Party ImpactAction100% third-party, 0 ms blockingFIX
FJS BundlesAction39 scripts, 612 KB unusedFIX
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://www.googletagmanager.com/gtag/js?id=G-4YY6NWZJSM&cx=c>m=4e64k0h2 | 177 KB | 67 KB (38%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-870914452&cx=c>m=4e64k0h2 | 144 KB | 62 KB (43%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-982386578&cx=c>m=4e64k0h2 | 137 KB | 62 KB (45%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=DC-15529822&cx=c>m=4e64k0h2 | 129 KB | 61 KB (47%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtag/js?id=DC-6108309&cx=c>m=4e64k0h2 | 129 KB | 61 KB (47%) | ✓ | 3rd |
| https://www.psu.edu/_next/static/chunks/2216-24f966dfb5453572.js | 90 KB | 61 KB (69%) | ✓ | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-P3SBL5 | 168 KB | 60 KB (36%) | ✓ | 3rd |
| https://www.psu.edu/_next/static/chunks/6016-82769d89c4b0e86a.js | 85 KB | 57 KB (68%) | ✓ | 3rd |
| https://www.psu.edu/_next/static/chunks/5168-5dae27bc77ab4fdd.js | 74 KB | 41 KB (60%) | ✓ | 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 InventoryAction80 resources · 5.4 MB · 612 KB savings availableFIX
~612.2 KiB of savings available
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 80 resources | 5.4 MiB | ||||||
FHTTP CachingActionNo cache headersFIX
No Cache-Control header
Adding a Cache-Control header can significantly improve repeat-visit performance.
BImage Optimization12 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
CJS Execution CostAction1130ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| Unattributable | 252ms | 5ms | 0ms | 3rd |
| https://script.hotjar.com/modules.6a0f3932cb1341a35c18.js | 222ms | 184ms | 5ms | 3rd |
| https://www.psu.edu/_next/static/chunks/1528-f6ff037bf6a98646.js | 154ms | 144ms | 3ms | 3rd |
| https://www.psu.edu/ | 144ms | 16ms | 3ms | 3rd |
| https://www.googletagmanager.com/gtm.js?id=GTM-P3SBL5 | 92ms | 76ms | 14ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=G-4YY6NWZJSM&cx=c>m=4e64k0h2 | 81ms | 68ms | 12ms | 3rd |
| https://www.psu.edu/_next/static/chunks/5416-e0797b595b278ec3.js | 70ms | 69ms | 1ms | 3rd |
| https://www.psu.edu/_next/static/chunks/1dd3208c-5dda107b194ce164.js | 63ms | 56ms | 4ms | 3rd |
| https://www.googletagmanager.com/gtag/js?id=AW-982386578&cx=c>m=4e64k0h2 | 51ms | 44ms | 7ms | 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 Loading4 fonts (111 KB)PASS
Web fonts
4
111 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 HintsNo optimization neededPASS
Network Waterfall80 requests over 32599msINFO
Third-Party Script CostPer-script blocking time, transfer cost, and cache headersINFO
| Script | Category | Execution | Transfer | Unused | Monthly Cost | Verdict |
|---|---|---|---|---|---|---|
Unattributable Unattributable | Other | 252ms | 0 KB | — | $3/mo | Costly |
Hotjar script.hotjar.com | Session Replay | 222ms | 57 KB | 47% | $3/mo | Costly |
www.psu.edu www.psu.edu | Other | 154ms | 33 KB | — | $2/mo | Optional |
www.psu.edu www.psu.edu | Other | 144ms | 39 KB | — | $2/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 92ms | 168 KB | 36% | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 81ms | 177 KB | 38% | $1/mo | Optional |
www.psu.edu www.psu.edu | Other | 70ms | 16 KB | — | $1/mo | Optional |
www.psu.edu www.psu.edu | Other | 63ms | 54 KB | — | $1/mo | Optional |
Google Tag Manager www.googletagmanager.com | Tag Manager | 51ms | 137 KB | 45% | $1/mo | Optional |
These scripts may cost more than they're worth
- Unattributable adds 252ms and costs ~$3/month
- Hotjar adds 222ms 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
Unattributable takes 252ms 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
Hotjar takes 222ms 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