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Performance

· 17 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
72
GRADE
C
FIX
6
REVIEW
2
PASS
7
INFO
2

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
60
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
100
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
100
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

3.08 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

8.18 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

329 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.

4.32 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.

10.68 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
17
7 PASS 2 REVIEW 6 FIX
F
Page Weight Budget
Action
4.3 MB transferred, 41 requests
FIX
4.3 MB transferred, 41 requests
Critical::
Page weighs 5.7 MB (4.3 MB transferred)
Warning::
Images are 3.4 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 3.4 MB
Warning::
JavaScript is 724 KB — consider code splitting or lazy loading
Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.
Got: 724 KB
Info::
41 HTTP requests
Info::
Estimated 0.89 g CO2 per page load
4.3 MB / 2.4 MB budget
4.3 MB transferred
41 requests
0.89 g CO2 per page load
Images 3.4 MiB 79%
JavaScript 724.2 KiB 17%
Fonts 121.5 KiB 3%
CSS 24.4 KiB 1%
HTML 23.2 KiB 1%
Other 6.7 KiB 0%
Other 693 B 0%
Other 595 B 0%
0 2.4 MB 4.9 MB
Over budget

Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.

Why this matters

Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.

Source: web.dev

Large JavaScript bundles delay interactivity. Split code by route or defer non-critical scripts.

Why this matters

JavaScript bundle is large — code-split routes and lazy-load off-screen components to defer.

Source: web.dev

D
Third-Party Impact
Action
100% third-party, 0 ms blocking
FIX
100% third-party, 0 ms blocking
Warning::
Third-party code accounts for 100% of page weight (4.3 MiB of 4.3 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
D
JS Execution Cost
Action
2003ms total JS execution
FIX
2003ms total JS execution
Warning::
https://www.wisc.edu/: 848ms CPU time
Warning::
https://www.googletagmanager.com/gtag/js?id=G-PLJ9...: 311ms CPU time
Warning::
Unattributable: 260ms CPU time
Warning::
https://www.googletagmanager.com/gtag/js?id=G-D04H...: 254ms CPU time
Info::
https://www.googletagmanager.com/gtm.js?id=GTM-N7G...: 184ms CPU time
Warning::
Third-party scripts: 2003ms (100% of total)

Main Thread Breakdown

Script Evaluation 35% Style & Layout 24% Other 24% Script Parsing & Compilation 9% Rendering 5%
ScriptTotalScriptingParse/CompileParty
https://www.wisc.edu/848ms25ms4ms3rd
https://www.googletagmanager.com/gtag/js?id=G-PLJ9E3ZY82&cx=c&gtm=4e64h1311ms241ms39ms3rd
Unattributable260ms6ms0ms3rd
https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERG254ms207ms45ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-N7GFX62184ms139ms35ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-TQ8DQJ487ms61ms25ms3rd
https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERG&cx=c&gtm=4e64h159ms23ms36ms3rd
D
JS Bundles
Action
9 scripts, 362 KB unused
FIX
9 scripts, 362 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-D04H...: 108 KB unused (70%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-TQ8...: 66 KB unused (55%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-D04H...: 64 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtag/js?id=G-PLJ9...: 63 KB unused (40%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-N7G...: 62 KB unused (50%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 362 KB
362 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERG&cx=c&gtm=4e64h1154 KB108 KB (70%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-TQ8DQJ4119 KB66 KB (55%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERG154 KB64 KB (41%)✓3rd
https://www.googletagmanager.com/gtag/js?id=G-PLJ9E3ZY82&cx=c&gtm=4e64h1156 KB63 KB (40%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-N7GFX62124 KB62 KB (50%)✓3rd
https://www.wisc.edu/js/redesign.b2edc13edf9eef87d18f54f90b3fb8eb.js3 KB—✓3rd
https://www.wisc.edu/js/uw-alerts.5f2d80a5abd5857da8ff06a623e147eb.js4 KB—✓3rd
https://cdn.wisc.cloud/cookie-consent/1.1.0/uwcookieconsent.min.js3 KB—✓3rd
https://img04.en25.com/i/elqCfg.min.js6 KB—✓3rd

Consider code splitting or tree shaking to reduce unused code.

Why this matters

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.

Why this matters

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.

Why this matters

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.

Why this matters

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.

Why this matters

This bundle has high unused code — code-split or tree-shake to ship only what executes.

Source: web.dev / Lighthouse coverage

D
Page Weight Inventory
Action
41 resources · 4.3 MB · 362 KB savings available
FIX
41 resources · 4.3 MB · 362 KB savings available
Warning::
Page weight 3.3 MB over 1MB target
Got: 4.3 MB Expected: ≤ 1 MB
Info::
~362 KB of savings available
Warning::
40 third-party resources (100% of weight)
Info::
7 resources over 200KB
41 resources · 4.3 MiB · 40 third-party 3.3 MiB over 1MB target
Image 79% · 3.4 MiB
JavaScript 17% · 724.2 KiB
Font 3% · 121.5 KiB
CSS 1% · 24.4 KiB
Document 1% · 24.2 KiB
Other 0% · 1.3 KiB

~362.0 KiB of savings available

Remove unused JavaScript: 362.0 KiB
F
HTTP Caching
Action
No cache headers
FIX
No cache headers
Warning::
No Cache-Control header found
Browsers will use heuristic caching, which can be unpredictable. Set explicit cache headers.

No Cache-Control header

Adding a Cache-Control header can significantly improve repeat-visit performance.

B
Image Optimization
16 images, 0 KB saveable
REVIEW
16 images, 0 KB saveable
Info::
All images are well-optimized
16 images 3.4 MB
0 oversized -0 KB
15 legacy format
0 missing dimensions CLS risk
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
Font Loading
5 fonts (122 KB)
PASS
5 fonts (122 KB)
Info::
5 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

5

122 KB total

Render-blocking

0

of 5

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s 7.0 s 8.0 s FCP 3.1 s LCP 8.2 shttps://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/redhat-text-latin.v13.woff2redhat-text-latin.v13.w... https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/redhat-text-latin.v13.woff2 — 27.6 KiB — 367 ms — font-display: swaphttps://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/redhat-display-latin.v14.woff2redhat-display-latin.v1... https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/redhat-display-latin.v14.woff2 — 28.6 KiB — 40 ms — font-display: swaphttps://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/libre-baskerville-700-latin.v14.woff2libre-baskerville-700-l... https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/libre-baskerville-700-latin.v14.woff2 — 17.9 KiB — 24 ms — font-display: swaphttps://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/libre-baskerville-400-latin.v14.woff2libre-baskerville-400-l... https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/libre-baskerville-400-latin.v14.woff2 — 17.4 KiB — 324 ms — font-display: swaphttps://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/redhat-text-italic-latin.v13.woff2redhat-text-italic-lati... https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/redhat-text-italic-latin.v13.woff2 — 29.9 KiB — 44 ms — font-display: swap
redhat-text-latin.v13.w... woff2 swap
Size 28 KB
Load time 367 ms
Start 1.1 s
Risk FOUT — text flashes from fallback to web font
redhat-display-latin.v1... woff2 swap
Size 29 KB
Load time 40 ms
Start 1.1 s
Risk FOUT — text flashes from fallback to web font
libre-baskerville-700-l... woff2 swap
Size 18 KB
Load time 24 ms
Start 1.1 s
Risk FOUT — text flashes from fallback to web font
libre-baskerville-400-l... woff2 swap
Size 17 KB
Load time 324 ms
Start 1.1 s
Risk FOUT — text flashes from fallback to web font
redhat-text-italic-lati... woff2 swap
Size 30 KB
Load time 44 ms
Start 1.1 s
Risk FOUT — text flashes from fallback to web font
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 Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
2 hints, 0 missing preconnects
PASS
2 hints, 0 missing preconnects
Info::
Page uses 2 resource hint(s)

Current Resource Hints

preconnect
1
preload
1
dns-prefetch
—
prefetch
—

2 resource hints configured

A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
Network Waterfall
41 requests over 2152ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s 7.0 s 8.0 s FCP 3.1 s LCP 8.2 shttps://wisc.edu// https://wisc.edu/ — 301 — 234 B — 374 ms — http/1.1https://www.wisc.edu/www.wisc.edu/ https://www.wisc.edu/ — 200 — 23.2 KiB — 227 ms — h2https://www.wisc.edu/images/hero/bascom-hill-spring-2025-880.jpgwww.wisc.edu/images/hero/bascom-hil... https://www.wisc.edu/images/hero/bascom-hill-spring-2025-880.jpg — 200 — 168.8 KiB — 60 ms — h2https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/fonts.csscdn.wisc.cloud/fonts/uw-rh-lb/0.0.1... https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/fonts.css — 200 — 885 B — 423 ms — h2https://www.wisc.edu/css/redesign.35588a9a443ae153e14a44a88430175b.csswww.wisc.edu/css/redesign.35588a9a4... https://www.wisc.edu/css/redesign.35588a9a443ae153e14a44a88430175b.css — 200 — 21.2 KiB — 26 ms — h2https://www.wisc.edu/css/uw_alerts.52f6ec0c5077e42907ca966bb4252b1e.csswww.wisc.edu/css/uw_alerts.52f6ec0c... https://www.wisc.edu/css/uw_alerts.52f6ec0c5077e42907ca966bb4252b1e.css — 200 — 826 B — 24 ms — h2https://www.wisc.edu/js/redesign.b2edc13edf9eef87d18f54f90b3fb8eb.jswww.wisc.edu/js/redesign.b2edc13edf... https://www.wisc.edu/js/redesign.b2edc13edf9eef87d18f54f90b3fb8eb.js — 200 — 3.3 KiB — 27 ms — h2https://www.wisc.edu/js/uw-alerts.5f2d80a5abd5857da8ff06a623e147eb.jswww.wisc.edu/js/uw-alerts.5f2d80a5a... https://www.wisc.edu/js/uw-alerts.5f2d80a5abd5857da8ff06a623e147eb.js — 200 — 4.1 KiB — 28 ms — h2https://cdn.wisc.cloud/cookie-consent/1.1.0/uwcookieconsent.min.jscdn.wisc.cloud/cookie-consent/1.1.0... https://cdn.wisc.cloud/cookie-consent/1.1.0/uwcookieconsent.min.js — 200 — 3.3 KiB — 68 ms — h2https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERGwww.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERG — 200 — 153.9 KiB — 147 ms — h2https://www.googletagmanager.com/gtm.js?id=GTM-N7GFX62www.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-N7GFX62 — 200 — 124.3 KiB — 45 ms — h2https://www.googletagmanager.com/gtm.js?id=GTM-TQ8DQJ4www.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-TQ8DQJ4 — 200 — 119.4 KiB — 81 ms — h3https://www.googletagmanager.com/gtag/js?id=G-PLJ9E3ZY82&cx=c&gtm=4e64h1www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-PLJ9E3ZY82&cx=c&gtm=4e64h1 — 200 — 156.0 KiB — 61 ms — h3https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERG&cx=c&gtm=4e64h1www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERG&cx=c&gtm=4e64h1 — 200 — 153.5 KiB — 61 ms — h3https://www.wisc.edu/css/print.85b35cb7d814b15abbc88d55dcda53c8.csswww.wisc.edu/css/print.85b35cb7d814... https://www.wisc.edu/css/print.85b35cb7d814b15abbc88d55dcda53c8.css — 200 — 1.6 KiB — 23 ms — h2https://www.wisc.edu/images/home/terrace-chairs-rainbow.jpgwww.wisc.edu/images/home/terrace-ch... https://www.wisc.edu/images/home/terrace-chairs-rainbow.jpg — 200 — 484.6 KiB — 56 ms — h2https://www.wisc.edu/images/quote-mark-red.svgwww.wisc.edu/images/quote-mark-red.... https://www.wisc.edu/images/quote-mark-red.svg — 200 — 1.1 KiB — 23 ms — h2https://www.wisc.edu/images/admissions/capitol-rainbow-1600x940.jpgwww.wisc.edu/images/admissions/capi... https://www.wisc.edu/images/admissions/capitol-rainbow-1600x940.jpg — 200 — 237.7 KiB — 47 ms — h2https://www.wisc.edu/images/geometric-bg-2.svgwww.wisc.edu/images/geometric-bg-2.... https://www.wisc.edu/images/geometric-bg-2.svg — 200 — 2.5 KiB — 41 ms — h2https://www.wisc.edu/images/news/AuthorPhoto_JP-credit-to-Emilio-Guede-Jr_-900x600.jpgwww.wisc.edu/images/news/AuthorPhot... https://www.wisc.edu/images/news/AuthorPhoto_JP-credit-to-Emilio-Guede-Jr_-900x600.jpg — 200 — 96.3 KiB — 43 ms — h2https://www.wisc.edu/images/news/2026-27-Go-Big-Read-4x3-1-608x456.jpgwww.wisc.edu/images/news/2026-27-Go... https://www.wisc.edu/images/news/2026-27-Go-Big-Read-4x3-1-608x456.jpg — 200 — 77.1 KiB — 35 ms — h2https://www.wisc.edu/images/news/block-by-block-county-map-608x456.jpgwww.wisc.edu/images/news/block-by-b... https://www.wisc.edu/images/news/block-by-block-county-map-608x456.jpg — 200 — 97.9 KiB — 53 ms — h2https://www.wisc.edu/images/news/Fall-Campus-2025-10-29TW-4021_4x3-608x456.jpgwww.wisc.edu/images/news/Fall-Campu... https://www.wisc.edu/images/news/Fall-Campus-2025-10-29TW-4021_4x3-608x456.jpg — 200 — 116.2 KiB — 53 ms — h2https://www.wisc.edu/images/news/Northern-Lights-2025-11-12TW-1041-1882x1411-1-608x456.jpgwww.wisc.edu/images/news/Northern-L... https://www.wisc.edu/images/news/Northern-Lights-2025-11-12TW-1041-1882x1411-1-608x456.jpg — 200 — 85.1 KiB — 76 ms — h2https://www.wisc.edu/images/home/salt2.webpwww.wisc.edu/images/home/salt2.webp https://www.wisc.edu/images/home/salt2.webp — 200 — 527.6 KiB — 78 ms — h2https://www.wisc.edu/images/home/discovering-stem-cells.jpgwww.wisc.edu/images/home/discoverin... https://www.wisc.edu/images/home/discovering-stem-cells.jpg — 200 — 392.2 KiB — 76 ms — h2https://www.wisc.edu/images/home/south-africa-prairie.jpgwww.wisc.edu/images/home/south-afri... https://www.wisc.edu/images/home/south-africa-prairie.jpg — 200 — 552.7 KiB — 83 ms — h2https://www.wisc.edu/images/home/dom-strings-blue-sky.jpgwww.wisc.edu/images/home/dom-string... https://www.wisc.edu/images/home/dom-strings-blue-sky.jpg — 200 — 221.2 KiB — 75 ms — h2https://www.wisc.edu/images/home/yellowstone-sunset.jpgwww.wisc.edu/images/home/yellowston... https://www.wisc.edu/images/home/yellowstone-sunset.jpg — 200 — 392.7 KiB — 74 ms — h2https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/redhat-text-latin.v13.woff2cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1... https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/redhat-text-latin.v13.woff2 — 200 — 27.6 KiB — 367 ms — h2
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s 7.0 s 8.0 s FCP 3.1 s LCP 8.2 shttps://wisc.edu// https://wisc.edu/ — 301 — 234 B — 374 ms — http/1.1https://www.wisc.edu/www.wisc.edu/ https://www.wisc.edu/ — 200 — 23.2 KiB — 227 ms — h2https://www.wisc.edu/images/hero/bascom-hill-spring-2025-880.jpgwww.wisc.edu/images/hero/bascom-hil... https://www.wisc.edu/images/hero/bascom-hill-spring-2025-880.jpg — 200 — 168.8 KiB — 60 ms — h2https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/fonts.csscdn.wisc.cloud/fonts/uw-rh-lb/0.0.1... https://cdn.wisc.cloud/fonts/uw-rh-lb/0.0.1/fonts.css — 200 — 885 B — 423 ms — h2https://www.wisc.edu/css/redesign.35588a9a443ae153e14a44a88430175b.csswww.wisc.edu/css/redesign.35588a9a4... https://www.wisc.edu/css/redesign.35588a9a443ae153e14a44a88430175b.css — 200 — 21.2 KiB — 26 ms — h2https://www.wisc.edu/css/uw_alerts.52f6ec0c5077e42907ca966bb4252b1e.csswww.wisc.edu/css/uw_alerts.52f6ec0c... https://www.wisc.edu/css/uw_alerts.52f6ec0c5077e42907ca966bb4252b1e.css — 200 — 826 B — 24 ms — h2https://www.wisc.edu/js/redesign.b2edc13edf9eef87d18f54f90b3fb8eb.jswww.wisc.edu/js/redesign.b2edc13edf... https://www.wisc.edu/js/redesign.b2edc13edf9eef87d18f54f90b3fb8eb.js — 200 — 3.3 KiB — 27 ms — h2https://www.wisc.edu/js/uw-alerts.5f2d80a5abd5857da8ff06a623e147eb.jswww.wisc.edu/js/uw-alerts.5f2d80a5a... https://www.wisc.edu/js/uw-alerts.5f2d80a5abd5857da8ff06a623e147eb.js — 200 — 4.1 KiB — 28 ms — h2https://cdn.wisc.cloud/cookie-consent/1.1.0/uwcookieconsent.min.jscdn.wisc.cloud/cookie-consent/1.1.0... https://cdn.wisc.cloud/cookie-consent/1.1.0/uwcookieconsent.min.js — 200 — 3.3 KiB — 68 ms — h2https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERGwww.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-D04HXCEERG — 200 — 153.9 KiB — 147 ms — h2https://www.googletagmanager.com/gtm.js?id=GTM-N7GFX62www.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-N7GFX62 — 200 — 124.3 KiB — 45 ms — 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https://region1.google-analytics.com/g/collect?v=2&tid=G-PLJ9E3ZY82&gtm=45je64h1v894063859z8894059498za20gzb894059498zd894059498&_p=1776797930604&gcd=13l3l3l2l1l1&npa=1&dma_cps=a&dma=1&_eu=Ag&are=1&cid=10396267.1776797931&frm=0&pscdl=noapi&rcb=10&sr=412x823&uaa=&uab=64&uafvl=Chromium%3B147.0.7727.101%7CNot.A%252FBrand%3B8.0.0.0&uam=moto%20g%20power%20(2022)&uamb=1&uap=Android&uapv=11.0&uaw=0&ul=en-us&_s=1&tag_exp=0~115938465~115938468~117266400~117384406~117512542~118128923&sid=1776797931&sct=1&seg=0&dl=https%3A%2F%2Fwww.wisc.edu%2F&dt=University%20of%20Wisconsin%E2%80%93Madison&en=page_view&_fv=1&_ss=1&tfd=1316 — 204 — 48 B — 29 ms — h2https://s1427524768.t.eloqua.com/visitor/v200/svrGP?pps=3&siteid=1427524768&ref2=elqNone&tzo=0&ms=334&optin=disableds1427524768.t.eloqua.com/visitor/v2... https://s1427524768.t.eloqua.com/visitor/v200/svrGP?pps=3&siteid=1427524768&ref2=elqNone&tzo=0&ms=334&optin=disabled — 302 — 825 B — 363 ms — 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HTML JavaScript CSS Images Fonts XHR/Fetch Other
Third-Party Script Cost
Per-script blocking time, transfer cost, and cache headers
INFO
100% of JavaScript execution is third-party
First-party Third-party 2003ms · 730KB · $27/mo
www.wisc.edu
Other
Costly
Execution 848ms
Transfer 23 KB
Monthly Cost $11/mo
Google Tag Manager
Tag Manager
Costly
Execution 311ms
Transfer 156 KB
Unused 40%
Monthly Cost $4/mo
Unattributable
Other
Costly
Execution 260ms
Transfer 0 KB
Monthly Cost $3/mo
Google Tag Manager
Tag Manager
Costly
Execution 254ms
Transfer 154 KB
Unused 41%
Monthly Cost $3/mo
Google Tag Manager
Tag Manager
Optional
Execution 184ms
Transfer 124 KB
Unused 50%
Monthly Cost $2/mo
Google Tag Manager
Tag Manager
Optional
Execution 87ms
Transfer 119 KB
Unused 55%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 59ms
Transfer 154 KB
Unused 70%
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • www.wisc.edu adds 848ms and costs ~$11/month
  • Google Tag Manager adds 311ms and costs ~$4/month
  • Unattributable adds 260ms and costs ~$3/month
  • Google Tag Manager adds 254ms and costs ~$3/month

100% of JavaScript execution time is spent on third-party scripts. Consider auditing which scripts are essential.

Why this matters

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.wisc.edu takes 848ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

Google Tag Manager takes 311ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

Unattributable takes 260ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

Google Tag Manager takes 254ms of CPU time. Consider loading it asynchronously or replacing it with a lighter alternative.

Why this matters

This script has high main-thread execution time — optimize hot paths or defer.

Source: web.dev

50% of Google Tag Manager's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

55% of Google Tag Manager's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

70% of Google Tag Manager's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

How third-party costs are calculated

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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