Skip to content
https://duke.edu

Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
74
GRADE
C
FIX
4
REVIEW
4
PASS
5
INFO
2

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

Mobile Desktop
74
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
99
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.

1.37 s

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

2.87 s

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

1 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.006

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

2.90 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.

3.45 s

Page Load Progression

1.0 s
2.1 s
3.1 s
4.1 s
5.1 s
6.2 s
7.2 s
8.2 s
Checks
15
5 PASS 4 REVIEW 4 FIX
F
Page Weight Budget
Action
5.4 MB transferred, 56 requests
FIX
5.4 MB transferred, 56 requests
Critical::
Page weighs 6.5 MB (5.4 MB transferred)
Warning::
Images are 1.7 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 1.7 MB
Info::
Fonts are 988 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 988 KB
Info::
56 HTTP requests
Info::
Estimated 1.1 g CO2 per page load
5.4 MB / 2.4 MB budget
5.4 MB transferred
56 requests
1.1 g CO2 per page load
Other 2.2 MiB 41%
Images 1.7 MiB 32%
Fonts 988.2 KiB 18%
JavaScript 386.9 KiB 7%
CSS 93.9 KiB 2%
HTML 37.0 KiB 1%
Other 1.3 KiB 0%
Other 828 B 0%
Other 547 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

Subset fonts to include only used characters, or switch to system font stacks.

Why this matters

Font payload is large — subset to used glyphs only, or fall back to system fonts (zero load time).

Source: web.dev font loading

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 (5.4 MiB of 5.4 MiB)
Info::
Third-party blocking time is low (0 ms)
100%
First-party Third-party
D
Page Weight Inventory
Action
56 resources · 5.4 MB · 148 KB savings available
FIX
56 resources · 5.4 MB · 148 KB savings available
Warning::
Page weight 4.4 MB over 1MB target
Got: 5.4 MB Expected: ≤ 1 MB
Info::
~148 KB of savings available
Warning::
55 third-party resources (100% of weight)
Info::
5 resources over 200KB
56 resources · 5.4 MiB · 55 third-party 4.4 MiB over 1MB target
Media 41% · 2.2 MiB
Image 32% · 1.7 MiB
Font 18% · 988.2 KiB
JavaScript 7% · 386.9 KiB
CSS 2% · 93.9 KiB
Document 1% · 37.2 KiB
Other 0% · 1.3 KiB

~147.7 KiB of savings available

Remove unused JavaScript: 147.7 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
15 images, 0 KB saveable
REVIEW
15 images, 0 KB saveable
Warning::
https://www.duke.edu/wp-content/plugins/duke-block... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
15 images 1.7 MB
0 oversized -0 KB
13 legacy format
1 missing dimensions CLS risk

Set explicit width and height to prevent CLS.

Why this matters

Image without explicit width/height — browser can't reserve space; CLS jumps when image loads.

Source: web.dev / Core Web Vitals

C
JS Execution Cost
Action
1052ms total JS execution
REVIEW
1052ms total JS execution
Warning::
https://www.duke.edu/: 721ms CPU time
Info::
Unattributable: 149ms CPU time
Info::
https://scripts.clarity.ms/0.8.60-beta/clarity.js: 71ms CPU time
Info::
https://www.googletagmanager.com/gtm.js?id=GTM-PSP...: 57ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-EFHN...: 54ms CPU time
Warning::
Third-party scripts: 1052ms (100% of total)

Main Thread Breakdown

Other 36% Style & Layout 27% Script Evaluation 20% Rendering 13%
ScriptTotalScriptingParse/CompileParty
https://www.duke.edu/721ms4ms0ms3rd
Unattributable149ms3ms0ms3rd
https://scripts.clarity.ms/0.8.60-beta/clarity.js71ms61ms2ms3rd
https://www.googletagmanager.com/gtm.js?id=GTM-PSPVTBK57ms45ms9ms3rd
https://www.googletagmanager.com/gtag/js?id=G-EFHNRXCSHV&cx=c&gtm=4e64h1h154ms43ms10ms3rd
B
JS Bundles
20 scripts, 148 KB unused
REVIEW
20 scripts, 148 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-EFHN...: 65 KB unused (43%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.googletagmanager.com/gtm.js?id=GTM-PSP...: 62 KB unused (47%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://www.duke.edu/wp-includes/js/jquery/jquery....: 20 KB unused (68%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 148 KB
148 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-EFHNRXCSHV&cx=c&gtm=4e64h1h1152 KB65 KB (43%)✓3rd
https://www.googletagmanager.com/gtm.js?id=GTM-PSPVTBK133 KB62 KB (47%)✓3rd
https://www.duke.edu/wp-includes/js/jquery/jquery.min.js?ver=3.7.130 KB20 KB (68%)✓3rd
https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/js/front-end.js?ver=d49a6e163b0c4115ba192 KB—✓3rd
https://www.clarity.ms/tag/qqq24l56vd1 KB—✓3rd
https://www.duke.edu/wp-content/plugins/duke-blocks/assets/js/duke-blocks-frontend.js?ver=17724841051 KB—✓3rd
https://www.duke.edu/wp-content/plugins/duke-blocks/build/duke-menu/view.js?ver=2ee6d6e39e96cf0add6b1 KB—✓3rd
https://www.duke.edu/wp-content/plugins/duke-blocks/build/hidden-content/view.js?ver=31d6cfe0d16ae931b73c0 KB—✓3rd
https://www.duke.edu/wp-content/plugins/duke-blocks/build/section-heading/view.js?ver=f8f2baec9ab8281305fd1 KB—✓3rd
https://www.duke.edu/wp-content/plugins/duke-alertbar/public/js/duke-alertbar-public.js?ver=1.0.01 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

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
4 fonts (988 KB)
PASS
4 fonts (988 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

988 KB total

Render-blocking

0

of 4

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 FCP 1.4 s LCP 2.9 shttps://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Regular.ttfQuattrocento-Regular.ttf https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Regular.ttf — 144.5 KiB — 795 ms — font-display: swaphttps://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/fonts/duke-icons.8c5c276b.ttfduke-icons.8c5c276b.ttf https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/fonts/duke-icons.8c5c276b.ttf — 20.4 KiB — 348 ms — font-display: swaphttps://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/montserrat/Montserrat-VariableFont_wght.ttfMontserrat-VariableFont... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/montserrat/Montserrat-VariableFont_wght.ttf — 672.7 KiB — 3.3 s — font-display: swaphttps://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Bold.ttfQuattrocento-Bold.ttf https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Bold.ttf — 150.6 KiB — 703 ms — font-display: swap
Quattrocento-Regular.ttf ttf swap
Size 145 KB
Load time 795 ms
Start 1.9 s
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
duke-icons.8c5c276b.ttf ttf swap
Size 20 KB
Load time 348 ms
Start 1.9 s
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
Montserrat-VariableFont... ttf swap
Size 673 KB
Load time 3.3 s
Start 1.9 s
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
Quattrocento-Bold.ttf ttf swap
Size 151 KB
Load time 703 ms
Start 1.9 s
Risk FOUT — text flashes from fallback to web font
  • Convert to woff2 for ~30% smaller file size
  • Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
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 ~780 KB and ~1560 ms

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
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
Network Waterfall
56 requests over 7665ms
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 1.4 s LCP 2.9 shttps://duke.edu// https://duke.edu/ — 302 — 193 B — 349 ms — http/1.1https://www.duke.edu/www.duke.edu/ https://www.duke.edu/ — 200 — 37.0 KiB — 470 ms — http/1.1https://www.duke.edu/wp-includes/blocks/image/style.min.css?ver=6.9.4www.duke.edu/wp-includes/blocks/ima... https://www.duke.edu/wp-includes/blocks/image/style.min.css?ver=6.9.4 — 200 — 1.8 KiB — 336 ms — http/1.1https://www.duke.edu/wp-includes/blocks/navigation/style.min.css?ver=6.9.4www.duke.edu/wp-includes/blocks/nav... https://www.duke.edu/wp-includes/blocks/navigation/style.min.css?ver=6.9.4 — 200 — 2.5 KiB — 347 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/duke-menu/style-index.css?ver=0.1.0www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/duke-menu/style-index.css?ver=0.1.0 — 200 — 4.3 KiB — 352 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/blocks/core-template-part.css?ver=6.9.4www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/blocks/core-template-part.css?ver=6.9.4 — 200 — 267 B — 354 ms — http/1.1https://www.duke.edu/wp-includes/blocks/cover/style.min.css?ver=6.9.4www.duke.edu/wp-includes/blocks/cov... https://www.duke.edu/wp-includes/blocks/cover/style.min.css?ver=6.9.4 — 200 — 2.0 KiB — 364 ms — http/1.1https://www.duke.edu/wp-includes/blocks/social-links/style.min.css?ver=6.9.4www.duke.edu/wp-includes/blocks/soc... https://www.duke.edu/wp-includes/blocks/social-links/style.min.css?ver=6.9.4 — 200 — 1.8 KiB — 451 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-alertbar/public/css/duke-alertbar-public.css?ver=1.0.0www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-alertbar/public/css/duke-alertbar-public.css?ver=1.0.0 — 200 — 420 B — 669 ms — http/1.1https://alertbar.oit.duke.edu/sites/all/themes/blackwell/css/alert.css?ver=1.0.0alertbar.oit.duke.edu/sites/all/the... https://alertbar.oit.duke.edu/sites/all/themes/blackwell/css/alert.css?ver=1.0.0 — 200 — 1.8 KiB — 569 ms — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/styles.css?ver=1.3www.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/styles.css?ver=1.3 — 200 — 79.0 KiB — 1.0 s — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/js/duke-blocks-frontend.js?ver=1772484105www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/js/duke-blocks-frontend.js?ver=1772484105 — 200 — 1.2 KiB — 694 ms — http/1.1https://www.duke.edu/wp-includes/js/jquery/jquery.min.js?ver=3.7.1www.duke.edu/wp-includes/js/jquery/... https://www.duke.edu/wp-includes/js/jquery/jquery.min.js?ver=3.7.1 — 200 — 30.0 KiB — 807 ms — http/1.1https://www.duke.edu/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.1www.duke.edu/wp-includes/js/jquery/... https://www.duke.edu/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.1 — 200 — 5.0 KiB — 702 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-alertbar/public/js/duke-alertbar-public.js?ver=1.0.0www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-alertbar/public/js/duke-alertbar-public.js?ver=1.0.0 — 200 — 1.2 KiB — 790 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/duke-wordmark-white.svgwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/duke-wordmark-white.svg — 200 — 5.2 KiB — 348 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/dt-logo.svgwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/dt-logo.svg — 200 — 13.2 KiB — 338 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/dd-white.svgwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/dd-white.svg — 200 — 7.0 KiB — 386 ms — http/1.1https://www.duke.edu/wp-content/uploads/2026/02/united-in-spirit-header.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/united-in-spirit-header.jpg — 200 — 251.3 KiB — 1.2 s — http/1.1https://alertbar.oit.duke.edu/alert.htmlalertbar.oit.duke.edu/alert.html https://alertbar.oit.duke.edu/alert.html — 200 — 402 B — 335 ms — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/js/front-end.js?ver=d49a6e163b0c4115ba19www.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/js/front-end.js?ver=d49a6e163b0c4115ba19 — 200 — 2.0 KiB — 773 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/duke-menu/view.js?ver=2ee6d6e39e96cf0add6bwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/duke-menu/view.js?ver=2ee6d6e39e96cf0add6b — 200 — 1.3 KiB — 1.1 s — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/hidden-content/view.js?ver=31d6cfe0d16ae931b73cwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/hidden-content/view.js?ver=31d6cfe0d16ae931b73c — 200 — 242 B — 1.1 s — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/section-heading/view.js?ver=f8f2baec9ab8281305fdwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/section-heading/view.js?ver=f8f2baec9ab8281305fd — 200 — 651 B — 1.2 s — http/1.1https://www.googletagmanager.com/gtm.js?id=GTM-PSPVTBKwww.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-PSPVTBK — 200 — 133.2 KiB — 452 ms — h2data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiPz4KPHN2ZyB4bWxucz0iaHR0c…data:image/svg+xml;base64,PD94bWwgd... data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiPz4KPHN2ZyB4bWxucz0iaHR0c… — 200 — 0 B — 0 ms — datadata:image/svg+xml;base64,PHN2ZyB3aWR0aD0iNjQ3IiBoZWlnaHQ9IjM2MiIgdmlld0JveD0iMCAwIDY0NyAzNjIiIGZpb…data:image/svg+xml;base64,PHN2ZyB3a... data:image/svg+xml;base64,PHN2ZyB3aWR0aD0iNjQ3IiBoZWlnaHQ9IjM2MiIgdmlld0JveD0iMCAwIDY0NyAzNjIiIGZpb… — 200 — 0 B — 1 ms — datahttps://www.duke.edu/wp-content/uploads/2026/02/duke-studens-spirit.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/duke-studens-spirit.jpg — 200 — 591.9 KiB — 1.9 s — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Regular.ttfwww.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Regular.ttf — 200 — 144.5 KiB — 795 ms — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/fonts/duke-icons.8c5c276b.ttfwww.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/fonts/duke-icons.8c5c276b.ttf — 200 — 20.4 KiB — 348 ms — http/1.1
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 1.4 s LCP 2.9 shttps://duke.edu// https://duke.edu/ — 302 — 193 B — 349 ms — http/1.1https://www.duke.edu/www.duke.edu/ https://www.duke.edu/ — 200 — 37.0 KiB — 470 ms — http/1.1https://www.duke.edu/wp-includes/blocks/image/style.min.css?ver=6.9.4www.duke.edu/wp-includes/blocks/ima... https://www.duke.edu/wp-includes/blocks/image/style.min.css?ver=6.9.4 — 200 — 1.8 KiB — 336 ms — http/1.1https://www.duke.edu/wp-includes/blocks/navigation/style.min.css?ver=6.9.4www.duke.edu/wp-includes/blocks/nav... https://www.duke.edu/wp-includes/blocks/navigation/style.min.css?ver=6.9.4 — 200 — 2.5 KiB — 347 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/duke-menu/style-index.css?ver=0.1.0www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/duke-menu/style-index.css?ver=0.1.0 — 200 — 4.3 KiB — 352 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/blocks/core-template-part.css?ver=6.9.4www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/blocks/core-template-part.css?ver=6.9.4 — 200 — 267 B — 354 ms — http/1.1https://www.duke.edu/wp-includes/blocks/cover/style.min.css?ver=6.9.4www.duke.edu/wp-includes/blocks/cov... https://www.duke.edu/wp-includes/blocks/cover/style.min.css?ver=6.9.4 — 200 — 2.0 KiB — 364 ms — http/1.1https://www.duke.edu/wp-includes/blocks/social-links/style.min.css?ver=6.9.4www.duke.edu/wp-includes/blocks/soc... https://www.duke.edu/wp-includes/blocks/social-links/style.min.css?ver=6.9.4 — 200 — 1.8 KiB — 451 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-alertbar/public/css/duke-alertbar-public.css?ver=1.0.0www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-alertbar/public/css/duke-alertbar-public.css?ver=1.0.0 — 200 — 420 B — 669 ms — http/1.1https://alertbar.oit.duke.edu/sites/all/themes/blackwell/css/alert.css?ver=1.0.0alertbar.oit.duke.edu/sites/all/the... https://alertbar.oit.duke.edu/sites/all/themes/blackwell/css/alert.css?ver=1.0.0 — 200 — 1.8 KiB — 569 ms — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/styles.css?ver=1.3www.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/styles.css?ver=1.3 — 200 — 79.0 KiB — 1.0 s — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/js/duke-blocks-frontend.js?ver=1772484105www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/js/duke-blocks-frontend.js?ver=1772484105 — 200 — 1.2 KiB — 694 ms — http/1.1https://www.duke.edu/wp-includes/js/jquery/jquery.min.js?ver=3.7.1www.duke.edu/wp-includes/js/jquery/... https://www.duke.edu/wp-includes/js/jquery/jquery.min.js?ver=3.7.1 — 200 — 30.0 KiB — 807 ms — http/1.1https://www.duke.edu/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.1www.duke.edu/wp-includes/js/jquery/... https://www.duke.edu/wp-includes/js/jquery/jquery-migrate.min.js?ver=3.4.1 — 200 — 5.0 KiB — 702 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-alertbar/public/js/duke-alertbar-public.js?ver=1.0.0www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-alertbar/public/js/duke-alertbar-public.js?ver=1.0.0 — 200 — 1.2 KiB — 790 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/duke-wordmark-white.svgwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/duke-wordmark-white.svg — 200 — 5.2 KiB — 348 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/dt-logo.svgwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/dt-logo.svg — 200 — 13.2 KiB — 338 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/dd-white.svgwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/assets/images/dd-white.svg — 200 — 7.0 KiB — 386 ms — http/1.1https://www.duke.edu/wp-content/uploads/2026/02/united-in-spirit-header.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/united-in-spirit-header.jpg — 200 — 251.3 KiB — 1.2 s — http/1.1https://alertbar.oit.duke.edu/alert.htmlalertbar.oit.duke.edu/alert.html https://alertbar.oit.duke.edu/alert.html — 200 — 402 B — 335 ms — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/js/front-end.js?ver=d49a6e163b0c4115ba19www.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/js/front-end.js?ver=d49a6e163b0c4115ba19 — 200 — 2.0 KiB — 773 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/duke-menu/view.js?ver=2ee6d6e39e96cf0add6bwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/duke-menu/view.js?ver=2ee6d6e39e96cf0add6b — 200 — 1.3 KiB — 1.1 s — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/hidden-content/view.js?ver=31d6cfe0d16ae931b73cwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/hidden-content/view.js?ver=31d6cfe0d16ae931b73c — 200 — 242 B — 1.1 s — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/section-heading/view.js?ver=f8f2baec9ab8281305fdwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/section-heading/view.js?ver=f8f2baec9ab8281305fd — 200 — 651 B — 1.2 s — http/1.1https://www.googletagmanager.com/gtm.js?id=GTM-PSPVTBKwww.googletagmanager.com/gtm.js?id=... https://www.googletagmanager.com/gtm.js?id=GTM-PSPVTBK — 200 — 133.2 KiB — 452 ms — h2data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiPz4KPHN2ZyB4bWxucz0iaHR0c…data:image/svg+xml;base64,PD94bWwgd... data:image/svg+xml;base64,PD94bWwgdmVyc2lvbj0iMS4wIiBlbmNvZGluZz0iVVRGLTgiPz4KPHN2ZyB4bWxucz0iaHR0c… — 200 — 0 B — 0 ms — datadata:image/svg+xml;base64,PHN2ZyB3aWR0aD0iNjQ3IiBoZWlnaHQ9IjM2MiIgdmlld0JveD0iMCAwIDY0NyAzNjIiIGZpb…data:image/svg+xml;base64,PHN2ZyB3a... data:image/svg+xml;base64,PHN2ZyB3aWR0aD0iNjQ3IiBoZWlnaHQ9IjM2MiIgdmlld0JveD0iMCAwIDY0NyAzNjIiIGZpb… — 200 — 0 B — 1 ms — datahttps://www.duke.edu/wp-content/uploads/2026/02/duke-studens-spirit.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/duke-studens-spirit.jpg — 200 — 591.9 KiB — 1.9 s — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Regular.ttfwww.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Regular.ttf — 200 — 144.5 KiB — 795 ms — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/fonts/duke-icons.8c5c276b.ttfwww.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/styles/fonts/duke-icons.8c5c276b.ttf — 200 — 20.4 KiB — 348 ms — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/montserrat/Montserrat-VariableFont_wght.ttfwww.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/montserrat/Montserrat-VariableFont_wght.ttf — 200 — 672.7 KiB — 3.3 s — http/1.1https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Bold.ttfwww.duke.edu/wp-content/themes/duke... https://www.duke.edu/wp-content/themes/duke-block-homepage/assets/fonts/quattrocento/Quattrocento-Bold.ttf — 200 — 150.6 KiB — 703 ms — http/1.1https://www.googletagmanager.com/gtag/js?id=G-EFHNRXCSHV&cx=c&gtm=4e64h1h1www.googletagmanager.com/gtag/js?id... https://www.googletagmanager.com/gtag/js?id=G-EFHNRXCSHV&cx=c&gtm=4e64h1h1 — 200 — 152.0 KiB — 63 ms — h2https://ssl.google-analytics.com/ga.jsssl.google-analytics.com/ga.js https://ssl.google-analytics.com/ga.js — 200 — 17.4 KiB — 76 ms — h2https://www.clarity.ms/tag/qqq24l56vdwww.clarity.ms/tag/qqq24l56vd https://www.clarity.ms/tag/qqq24l56vd — 200 — 848 B — 113 ms — http/1.1https://region1.google-analytics.com/g/collect?v=2&tid=G-EFHNRXCSHV&gtm=45je64h1h1v869443301z8866128375za20gzb866128375zd866128375&_p=1776798781860&gcd=13l3l3l2l1l1&npa=1&dma_cps=a&dma=1&are=1&cid=1600695345.1776798782&frm=0&pscdl=noapi&rcb=11&sr=800x600&uaa=x86&uab=64&uafvl=Chromium%3B147.0.7727.101%7CNot.A%252FBrand%3B8.0.0.0&uam=&uamb=0&uap=macOS&uapv=10.15.7&uaw=0&ul=en-us&_s=1&tag_exp=0~115938465~115938469~117266401~117384405&sid=1776798782&sct=1&seg=0&dl=https%3A%2F%2Fwww.duke.edu%2F&dt=Duke%20University%20-%20Fueled%20by%20creativity%2C%20informed%20by%20scholarship&en=page_view&_fv=1&_nsi=1&_ss=1&tfd=2393region1.google-analytics.com/g/coll... https://region1.google-analytics.com/g/collect?v=2&tid=G-EFHNRXCSHV&gtm=45je64h1h1v869443301z8866128375za20gzb866128375zd866128375&_p=1776798781860&gcd=13l3l3l2l1l1&npa=1&dma_cps=a&dma=1&are=1&cid=1600695345.1776798782&frm=0&pscdl=noapi&rcb=11&sr=800x600&uaa=x86&uab=64&uafvl=Chromium%3B147.0.7727.101%7CNot.A%252FBrand%3B8.0.0.0&uam=&uamb=0&uap=macOS&uapv=10.15.7&uaw=0&ul=en-us&_s=1&tag_exp=0~115938465~115938469~117266401~117384405&sid=1776798782&sct=1&seg=0&dl=https%3A%2F%2Fwww.duke.edu%2F&dt=Duke%20University%20-%20Fueled%20by%20creativity%2C%20informed%20by%20scholarship&en=page_view&_fv=1&_nsi=1&_ss=1&tfd=2393 — 204 — 547 B — 89 ms — h2https://ssl.google-analytics.com/r/__utm.gif?utmwv=5.7.2&utms=1&utmn=569974589&utmhn=www.duke.edu&utmcs=UTF-8&utmsr=800x600&utmvp=1350x940&utmsc=24-bit&utmul=en-us&utmje=0&utmfl=-&utmdt=Duke%20University%20-%20Fueled%20by%20creativity%2C%20informed%20by%20scholarship&utmhid=430560303&utmr=-&utmp=%2F&utmht=1776798782509&utmac=UA-3896341-5&utmgtm=45He64h1h1n81PSPVTBKv866128375za200zd866128375&utmcc=__utma%3D76785792.1600695345.1776798782.1776798783.1776798783.1%3B%2B__utmz%3D76785792.1776798783.1.1.utmcsr%3D(direct)%7Cutmccn%3D(direct)%7Cutmcmd%3D(none)%3B&utmjid=765035359&utmredir=1&utmu=qmAgAABAAAGBAAAAAgABAAAE~ssl.google-analytics.com/r/__utm.gi... https://ssl.google-analytics.com/r/__utm.gif?utmwv=5.7.2&utms=1&utmn=569974589&utmhn=www.duke.edu&utmcs=UTF-8&utmsr=800x600&utmvp=1350x940&utmsc=24-bit&utmul=en-us&utmje=0&utmfl=-&utmdt=Duke%20University%20-%20Fueled%20by%20creativity%2C%20informed%20by%20scholarship&utmhid=430560303&utmr=-&utmp=%2F&utmht=1776798782509&utmac=UA-3896341-5&utmgtm=45He64h1h1n81PSPVTBKv866128375za200zd866128375&utmcc=__utma%3D76785792.1600695345.1776798782.1776798783.1776798783.1%3B%2B__utmz%3D76785792.1776798783.1.1.utmcsr%3D(direct)%7Cutmccn%3D(direct)%7Cutmcmd%3D(none)%3B&utmjid=765035359&utmredir=1&utmu=qmAgAABAAAGBAAAAAgABAAAE~ — 200 — 440 B — 25 ms — h2https://scripts.clarity.ms/0.8.60-beta/clarity.jsscripts.clarity.ms/0.8.60-beta/clar... https://scripts.clarity.ms/0.8.60-beta/clarity.js — 200 — 25.0 KiB — 128 ms — h2https://b.clarity.ms/collectb.clarity.ms/collect https://b.clarity.ms/collect — 204 — 276 B — 526 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/tabs-list/view.js?ver=31d6cfe0d16ae931b73cwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/tabs-list/view.js?ver=31d6cfe0d16ae931b73c — 200 — 242 B — 332 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/tabs/view.js?ver=d0d6a6cb8b5471cecf07www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/tabs/view.js?ver=d0d6a6cb8b5471cecf07 — 200 — 988 B — 330 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/story-card/view.js?ver=d36e991ddd7a8169663dwww.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/story-card/view.js?ver=d36e991ddd7a8169663d — 200 — 580 B — 363 ms — http/1.1https://www.duke.edu/wp-content/plugins/duke-blocks/build/video/view.js?ver=f05780a798ab99b93e02www.duke.edu/wp-content/plugins/duk... https://www.duke.edu/wp-content/plugins/duke-blocks/build/video/view.js?ver=f05780a798ab99b93e02 — 200 — 1.1 KiB — 341 ms — http/1.1https://www.duke.edu/wp-content/uploads/2026/02/indigenous-superheroes.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/indigenous-superheroes.jpg — 200 — 192.1 KiB — 905 ms — http/1.1https://www.duke.edu/wp-content/uploads/2026/02/gaza-kids.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/gaza-kids.jpg — 200 — 222.9 KiB — 1.2 s — http/1.1https://www.duke.edu/wp-content/uploads/2026/02/scheyer-turek-blue-chair-2.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/scheyer-turek-blue-chair-2.jpg — 200 — 68.3 KiB — 670 ms — http/1.1https://www.duke.edu/wp-content/uploads/2026/02/student-athletes-768x576.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/student-athletes-768x576.jpg — 200 — 148.9 KiB — 949 ms — http/1.1https://www.youtube.com/iframe_apiwww.youtube.com/iframe_api https://www.youtube.com/iframe_api — 200 — 3.2 KiB — 93 ms — h2https://www.youtube.com/s/player/218d9d92/www-widgetapi.vflset/www-widgetapi.jswww.youtube.com/s/player/218d9d92/w... https://www.youtube.com/s/player/218d9d92/www-widgetapi.vflset/www-widgetapi.js — 200 — 10.6 KiB — 29 ms — h2https://www.duke.edu/wp-content/uploads/2026/02/science-club-illustration-1-768x512.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/science-club-illustration-1-768x512.jpg — 200 — 42.1 KiB — 559 ms — http/1.1https://www.duke.edu/wp-content/uploads/2026/02/160814_goodson029-1536x468.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/160814_goodson029-1536x468.jpg — 200 — 138.1 KiB — 889 ms — http/1.1https://www.duke.edu/wp-content/uploads/2026/02/undergraduates-majors-768x512.jpgwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/undergraduates-majors-768x512.jpg — 200 — 104.7 KiB — 1.0 s — http/1.1https://www.duke.edu/wp-content/uploads/2026/02/Header_v3_1.mp4www.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2026/02/Header_v3_1.mp4 — 206 — 2.2 MiB — 356 ms — http/1.1https://b.clarity.ms/collectb.clarity.ms/collect https://b.clarity.ms/collect — 204 — 276 B — 109 ms — http/1.1https://www.duke.edu/wp-content/uploads/2025/12/cropped-dfavicon-1-32x32.pngwww.duke.edu/wp-content/uploads/202... https://www.duke.edu/wp-content/uploads/2025/12/cropped-dfavicon-1-32x32.png — 200 — 1.1 KiB — 339 ms — http/1.1https://b.clarity.ms/collectb.clarity.ms/collect https://b.clarity.ms/collect — 204 — 276 B — 100 ms — http/1.1
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 1052ms · 347KB · $14/mo
www.duke.edu
Other
Costly
Execution 721ms
Transfer 37 KB
Monthly Cost $10/mo
Unattributable
Other
Optional
Execution 149ms
Transfer 0 KB
Monthly Cost $2/mo
Microsoft Clarity
Session Replay
Optional
Execution 71ms
Transfer 25 KB
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 57ms
Transfer 133 KB
Unused 47%
Monthly Cost $1/mo
Google Tag Manager
Tag Manager
Optional
Execution 54ms
Transfer 152 KB
Unused 43%
Monthly Cost $1/mo

These scripts may cost more than they're worth

  • www.duke.edu adds 721ms and costs ~$10/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.duke.edu takes 721ms 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

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.

Send Feedback