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Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
79
GRADE
C
FIX
2
REVIEW
5
PASS
6
INFO
2

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

Mobile Desktop
73
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
95
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.
85
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.

537 ms

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

3.46 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.

0.038

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

3.27 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.

3.49 s

Page Load Progression

1.2 s
2.4 s
3.7 s
4.9 s
6.1 s
7.3 s
8.6 s
9.8 s
Checks
15
6 PASS 5 REVIEW 2 FIX
F
Page Weight Budget
Action
4.0 MB transferred, 52 requests
FIX
4.0 MB transferred, 52 requests
Critical::
Page weighs 5.4 MB (4.0 MB transferred)
Warning::
Images are 3.3 MB — compress or use modern formats
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Got: 3.3 MB
Info::
Fonts are 358 KB — consider subsetting or using system fonts
Subset fonts to include only used characters, or switch to system font stacks.
Got: 358 KB
Info::
52 HTTP requests
Info::
Estimated 0.85 g CO2 per page load
4.0 MB / 2.4 MB budget
4.0 MB transferred
52 requests
0.85 g CO2 per page load
Images 3.3 MiB 82%
Fonts 357.9 KiB 9%
JavaScript 342.0 KiB 8%
CSS 46.3 KiB 1%
HTML 9.8 KiB 0%
Other 6.0 KiB 0%
Other 1013 B 0%
Other 893 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

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.

C
Image Optimization
Action
17 images, 0 KB saveable
REVIEW
17 images, 0 KB saveable
Warning::
https://cdc.gov/homepage/images/banner/outbreak.jp... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdc.gov/homepage/images/Diagnosis-for-Flu.... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdc.gov/homepage/images/banner/measles-hp.... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdc.gov/TemplatePackage/5.0/img/logo/cdc-l... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdc.gov/homepage/images/banner/raw-cheese-... is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
Warning::
https://cdc.gov/homepage/images/science-cdc.jpg is missing width/height — may cause layout shift
Set explicit width and height to prevent CLS.
17 images 3.3 MB
0 oversized -0 KB
16 legacy format
6 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

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

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

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

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

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
1123ms total JS execution
REVIEW
1123ms total JS execution
Warning::
https://cdc.gov/: 487ms CPU time
Info::
https://cdc.gov/TemplatePackage/5.0/js/homepage/cd...: 222ms CPU time
Info::
Unattributable: 194ms CPU time
Info::
https://cdc.gov/TemplatePackage/5.0/js/libs/wow.mi...: 149ms CPU time
Info::
https://www.googletagmanager.com/gtag/js?id=G-CSLL...: 71ms CPU time
Info::
Third-party scripts: 265ms (24% of total)

Main Thread Breakdown

Script Evaluation 36% Other 34% Style & Layout 15% Rendering 9%
ScriptTotalScriptingParse/CompileParty
https://cdc.gov/487ms1ms0ms1st
https://cdc.gov/TemplatePackage/5.0/js/homepage/cdc-hp-2024.min.js?_=04929222ms204ms0ms1st
Unattributable194ms8ms0ms3rd
https://cdc.gov/TemplatePackage/5.0/js/libs/wow.min.js?_=04929149ms90ms0ms1st
https://www.googletagmanager.com/gtag/js?id=G-CSLL4ZEK4L71ms60ms11ms3rd
B
JS Bundles
14 scripts, 126 KB unused
REVIEW
14 scripts, 126 KB unused
Warning::
https://www.googletagmanager.com/gtag/js?id=G-CSLL...: 60 KB unused (41%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdc.gov/TemplatePackage/contrib/libs/jquer...: 46 KB unused (55%)
Consider code splitting or tree shaking to reduce unused code.
Warning::
https://cdc.gov/TemplatePackage/contrib/libs/jquer...: unminified — 41 KB could be saved
Warning::
https://cdc.gov/TemplatePackage/5.0/js/app.min.js?...: 20 KB unused (63%)
Consider code splitting or tree shaking to reduce unused code.
Info::
Total unused JavaScript: 126 KB
126 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://www.googletagmanager.com/gtag/js?id=G-CSLL4ZEK4L147 KB60 KB (41%)✓3rd
https://cdc.gov/TemplatePackage/contrib/libs/jquery/latest/jquery.js?_=0492983 KB46 KB (55%)✗1st
https://cdc.gov/TemplatePackage/5.0/js/app.min.js?_=0492933 KB20 KB (63%)✓1st
https://cdc.gov/TemplatePackage/5.0/js/homepage/cdc-hp-2024.min.js?_=049294 KB—✓1st
https://cdc.gov/TemplatePackage/contrib/libs/bootstrap/5x/bootstrap.bundle.min.js?_=0492924 KB—✓1st
https://cdc.gov/TemplatePackage/5.0/js/libs/wow.min.js?_=049293 KB—✓1st
https://www.cdc.gov/JScript/dmat/cdc-dmat.min.js?account=cdcgov&_=0887111 KB—✓3rd
https://cdc.gov/config/cdc_config.js1 KB—✓1st
https://cdc.gov/homepage/hp2024.js1 KB—✓1st
https://www.cdc.gov/TemplatePackage/contrib/libs/dompurify/latest/purify.min.js9 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
Page Weight Inventory
Action
52 resources · 4.0 MB · 126 KB savings available
REVIEW
52 resources · 4.0 MB · 126 KB savings available
Warning::
Page weight 3.0 MB over 1MB target
Got: 4.0 MB Expected: ≤ 1 MB
Info::
~126 KB of savings available
Info::
11 third-party resources (5% of weight)
Info::
6 resources over 200KB
52 resources · 4.0 MiB · 11 third-party 3.0 MiB over 1MB target
Image 82% · 3.3 MiB
Font 9% · 357.9 KiB
JavaScript 8% · 342.0 KiB
CSS 1% · 46.3 KiB
Document 0% · 9.8 KiB
Other 0% · 5.9 KiB

~126.0 KiB of savings available

Remove unused JavaScript: 126.0 KiB
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

A+
Third-Party Impact
5% third-party, 0 ms blocking
PASS
5% third-party, 0 ms blocking
Info::
Third-party code accounts for 5% of page weight (187.2 KiB of 4.0 MiB)
Info::
Third-party blocking time is low (0 ms)
95%
First-party Third-party
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
10 fonts (358 KB)
PASS
10 fonts (358 KB)
Info::
10 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

10

358 KB total

Render-blocking

0

of 10

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 FCP 537 ms LCP 3.5 shttps://cdc.gov/TemplatePackage/5.0/fonts/nunito.400.woff2nunito.400.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/nunito.400.woff2 — 44.3 KiB — 10 ms — font-display: swaphttps://cdc.gov/TemplatePackage/5.0/fonts/poppins.300.woff2poppins.300.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/poppins.300.woff2 — 50.9 KiB — 11 ms — font-display: swaphttps://cdc.gov/TemplatePackage/5.0/fonts/cdc-fa-light.woff2?_=28598cdc-fa-light.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/cdc-fa-light.woff2?_=28598 — 14.8 KiB — 11 ms — font-display: swaphttps://cdc.gov/TemplatePackage/5.0/fonts/cdc-fa-regular.woff2?_=28598cdc-fa-regular.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/cdc-fa-regular.woff2?_=28598 — 13.6 KiB — 16 ms — font-display: swaphttps://cdc.gov/TemplatePackage/5.0/fonts/poppins.400.woff2poppins.400.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/poppins.400.woff2 — 51.0 KiB — 17 ms — font-display: swaphttps://cdc.gov/TemplatePackage/5.0/fonts/nunito.500.woff2nunito.500.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/nunito.500.woff2 — 44.4 KiB — 17 ms — font-display: swaphttps://cdc.gov/TemplatePackage/5.0/fonts/nunito.600.woff2nunito.600.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/nunito.600.woff2 — 44.6 KiB — 18 ms — font-display: swaphttps://cdc.gov/TemplatePackage/5.0/fonts/poppins.500.woff2poppins.500.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/poppins.500.woff2 — 50.4 KiB — 294 ms — font-display: swaphttps://cdc.gov/TemplatePackage/5.0/fonts/cdc-fa-solid.woff2?_=28598cdc-fa-solid.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/cdc-fa-solid.woff2?_=28598 — 11.5 KiB — 291 ms — font-display: swaphttps://cdc.gov/TemplatePackage/5.0/fonts/cdc-icons.woff2?_=28598cdc-icons.woff2 https://cdc.gov/TemplatePackage/5.0/fonts/cdc-icons.woff2?_=28598 — 32.4 KiB — 18 ms — font-display: swap
nunito.400.woff2 woff2 swap
Size 44 KB
Load time 10 ms
Start 197 ms
Risk FOUT — text flashes from fallback to web font
poppins.300.woff2 woff2 swap
Size 51 KB
Load time 11 ms
Start 198 ms
Risk FOUT — text flashes from fallback to web font
cdc-fa-light.woff2 woff2 swap
Size 15 KB
Load time 11 ms
Start 198 ms
Risk FOUT — text flashes from fallback to web font
cdc-fa-regular.woff2 woff2 swap
Size 14 KB
Load time 16 ms
Start 198 ms
Risk FOUT — text flashes from fallback to web font
poppins.400.woff2 woff2 swap
Size 51 KB
Load time 17 ms
Start 198 ms
Risk FOUT — text flashes from fallback to web font
nunito.500.woff2 woff2 swap
Size 44 KB
Load time 17 ms
Start 201 ms
Risk FOUT — text flashes from fallback to web font
nunito.600.woff2 woff2 swap
Size 45 KB
Load time 18 ms
Start 201 ms
Risk FOUT — text flashes from fallback to web font
poppins.500.woff2 woff2 swap
Size 50 KB
Load time 294 ms
Start 201 ms
Risk FOUT — text flashes from fallback to web font
cdc-fa-solid.woff2 woff2 swap
Size 12 KB
Load time 291 ms
Start 201 ms
Risk FOUT — text flashes from fallback to web font
cdc-icons.woff2 woff2 swap
Size 32 KB
Load time 18 ms
Start 203 ms
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
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
Network Waterfall
52 requests over 5703ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s FCP 537 ms LCP 3.5 shttps://cdc.gov// https://cdc.gov/ — 200 — 9.8 KiB — 35 ms — h2https://cdc.gov/TemplatePackage/5.0/css/homepage/hp-2024.min.css?_=04929/TemplatePackage/5.0/css/homepage/h... https://cdc.gov/TemplatePackage/5.0/css/homepage/hp-2024.min.css?_=04929 — 200 — 43.2 KiB — 14 ms — h2https://www.cdc.gov/JScript/dmat/cdc-dmat.min.js?account=cdcgov&_=08871www.cdc.gov/JScript/dmat/cdc-dmat.m... https://www.cdc.gov/JScript/dmat/cdc-dmat.min.js?account=cdcgov&_=08871 — 200 — 11.4 KiB — 55 ms — h2https://cdc.gov/homepage/hp2024.css/homepage/hp2024.css https://cdc.gov/homepage/hp2024.css — 200 — 1.2 KiB — 6 ms — h2https://cdc.gov/TemplatePackage/5.0/js/modules/banner.js?20260409/TemplatePackage/5.0/js/modules/ban... https://cdc.gov/TemplatePackage/5.0/js/modules/banner.js?20260409 — 200 — 2.9 KiB — 7 ms — h2https://cdc.gov/TemplatePackage/5.0/img/uswds/icon-dot-gov.svg/TemplatePackage/5.0/img/uswds/icon... https://cdc.gov/TemplatePackage/5.0/img/uswds/icon-dot-gov.svg — 200 — 756 B — 9 ms — h2https://cdc.gov/TemplatePackage/5.0/img/uswds/icon-https.svg/TemplatePackage/5.0/img/uswds/icon... https://cdc.gov/TemplatePackage/5.0/img/uswds/icon-https.svg — 200 — 703 B — 10 ms — h2https://cdc.gov/TemplatePackage/5.0/img/logo/logo2.svg/TemplatePackage/5.0/img/logo/logo2... https://cdc.gov/TemplatePackage/5.0/img/logo/logo2.svg — 200 — 1.6 KiB — 5 ms — h2https://cdc.gov/TemplatePackage/5.0/img/logo/cdc-logo-tag-right.svg/TemplatePackage/5.0/img/logo/cdc-l... https://cdc.gov/TemplatePackage/5.0/img/logo/cdc-logo-tag-right.svg — 200 — 5.0 KiB — 7 ms — h2https://cdc.gov/homepage/images/Diagnosis-for-Flu.jpg/homepage/images/Diagnosis-for-Flu.... https://cdc.gov/homepage/images/Diagnosis-for-Flu.jpg — 200 — 194.4 KiB — 8 ms — h2https://cdc.gov/config/cdc_config.js/config/cdc_config.js https://cdc.gov/config/cdc_config.js — 200 — 528 B — 7 ms — h2https://cdc.gov/TemplatePackage/contrib/libs/bootstrap/5x/bootstrap.bundle.min.js?_=04929/TemplatePackage/contrib/libs/boots... https://cdc.gov/TemplatePackage/contrib/libs/bootstrap/5x/bootstrap.bundle.min.js?_=04929 — 200 — 23.6 KiB — 6 ms — h2https://cdc.gov/TemplatePackage/contrib/libs/jquery/latest/jquery.js?_=04929/TemplatePackage/contrib/libs/jquer... https://cdc.gov/TemplatePackage/contrib/libs/jquery/latest/jquery.js?_=04929 — 200 — 83.5 KiB — 8 ms — h2https://cdc.gov/TemplatePackage/5.0/js/libs/wow.min.js?_=04929/TemplatePackage/5.0/js/libs/wow.mi... https://cdc.gov/TemplatePackage/5.0/js/libs/wow.min.js?_=04929 — 200 — 3.1 KiB — 4 ms — h2https://cdc.gov/TemplatePackage/5.0/js/homepage/cdc-hp-2024.min.js?_=04929/TemplatePackage/5.0/js/homepage/cd... https://cdc.gov/TemplatePackage/5.0/js/homepage/cdc-hp-2024.min.js?_=04929 — 200 — 4.3 KiB — 5 ms — h2https://cdc.gov/TemplatePackage/5.0/js/app.min.js?_=04929/TemplatePackage/5.0/js/app.min.js?... https://cdc.gov/TemplatePackage/5.0/js/app.min.js?_=04929 — 200 — 32.7 KiB — 9 ms — h2https://cdc.gov/homepage/hp2024.js/homepage/hp2024.js https://cdc.gov/homepage/hp2024.js — 200 — 940 B — 12 ms — h2https://cdc.gov/TemplatePackage/5.0/json/manifest.json/TemplatePackage/5.0/json/manifest.... https://cdc.gov/TemplatePackage/5.0/json/manifest.json — 200 — 1013 B — 17 ms — h2https://cdc.gov/TemplatePackage/5.0/img/uswds/us_flag_small.png/TemplatePackage/5.0/img/uswds/us_f... https://cdc.gov/TemplatePackage/5.0/img/uswds/us_flag_small.png — 200 — 898 B — 12 ms — h2https://cdc.gov/TemplatePackage/5.0/img/homepage/outbreak.svg/TemplatePackage/5.0/img/homepage/o... https://cdc.gov/TemplatePackage/5.0/img/homepage/outbreak.svg — 200 — 186.6 KiB — 33 ms — h2https://cdc.gov/TemplatePackage/5.0/img/homepage/aboutcdc.png/TemplatePackage/5.0/img/homepage/a... https://cdc.gov/TemplatePackage/5.0/img/homepage/aboutcdc.png — 200 — 242.8 KiB — 33 ms — h2https://cdc.gov/homepage/images/banner/raw-cheese-4.jpg/homepage/images/banner/raw-cheese-... https://cdc.gov/homepage/images/banner/raw-cheese-4.jpg — 200 — 392.2 KiB — 306 ms — h2https://cdc.gov/homepage/images/banner/measles-hp.jpg/homepage/images/banner/measles-hp.... https://cdc.gov/homepage/images/banner/measles-hp.jpg — 200 — 570.2 KiB — 330 ms — h2https://cdc.gov/homepage/images/banner/outbreak.jpg/homepage/images/banner/outbreak.jp... https://cdc.gov/homepage/images/banner/outbreak.jpg — 200 — 468.9 KiB — 329 ms — h2https://cdc.gov/TemplatePackage/5.0/img/homepage/mmwr.png/TemplatePackage/5.0/img/homepage/m... https://cdc.gov/TemplatePackage/5.0/img/homepage/mmwr.png — 200 — 46.2 KiB — 25 ms — h2https://cdc.gov/TemplatePackage/5.0/img/homepage/eid.png/TemplatePackage/5.0/img/homepage/e... https://cdc.gov/TemplatePackage/5.0/img/homepage/eid.png — 200 — 35.6 KiB — 27 ms — h2https://cdc.gov/TemplatePackage/5.0/img/homepage/pcd.png/TemplatePackage/5.0/img/homepage/p... https://cdc.gov/TemplatePackage/5.0/img/homepage/pcd.png — 200 — 49.1 KiB — 30 ms — h2https://cdc.gov/homepage/images/science-cdc.jpg/homepage/images/science-cdc.jpg https://cdc.gov/homepage/images/science-cdc.jpg — 200 — 336.4 KiB — 39 ms — h2https://cdc.gov/TemplatePackage/5.0/css/print.min.css?_=04929/TemplatePackage/5.0/css/print.min.... https://cdc.gov/TemplatePackage/5.0/css/print.min.css?_=04929 — 200 — 1.9 KiB — 35 ms — h2https://cdc.gov/TemplatePackage/5.0/img/homepage/background-swirl.svg/TemplatePackage/5.0/img/homepage/b... https://cdc.gov/TemplatePackage/5.0/img/homepage/background-swirl.svg — 200 — 845.9 KiB — 34 ms — h2
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s FCP 537 ms LCP 3.5 shttps://cdc.gov// https://cdc.gov/ — 200 — 9.8 KiB — 35 ms — h2https://cdc.gov/TemplatePackage/5.0/css/homepage/hp-2024.min.css?_=04929/TemplatePackage/5.0/css/homepage/h... https://cdc.gov/TemplatePackage/5.0/css/homepage/hp-2024.min.css?_=04929 — 200 — 43.2 KiB — 14 ms — h2https://www.cdc.gov/JScript/dmat/cdc-dmat.min.js?account=cdcgov&_=08871www.cdc.gov/JScript/dmat/cdc-dmat.m... https://www.cdc.gov/JScript/dmat/cdc-dmat.min.js?account=cdcgov&_=08871 — 200 — 11.4 KiB — 55 ms — h2https://cdc.gov/homepage/hp2024.css/homepage/hp2024.css https://cdc.gov/homepage/hp2024.css — 200 — 1.2 KiB — 6 ms — h2https://cdc.gov/TemplatePackage/5.0/js/modules/banner.js?20260409/TemplatePackage/5.0/js/modules/ban... https://cdc.gov/TemplatePackage/5.0/js/modules/banner.js?20260409 — 200 — 2.9 KiB — 7 ms — h2https://cdc.gov/TemplatePackage/5.0/img/uswds/icon-dot-gov.svg/TemplatePackage/5.0/img/uswds/icon... 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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
24% of JavaScript execution is third-party
First-party Third-party 265ms · 147KB · $4/mo
Unattributable
Other
Optional
Execution 194ms
Transfer 0 KB
Monthly Cost $3/mo
Google Tag Manager
Tag Manager
Optional
Execution 71ms
Transfer 147 KB
Unused 41%
Monthly Cost $1/mo

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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