Performance

· 15 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.

SCORE

GRADE

FIX

REVIEW

PASS

INFO

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

Mobile Desktop

Performance

Accessibility

Best Practices

SEO

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.

2.51 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.

0.049

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

1.46 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.

2.51 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

7 PASS 2 REVIEW 4 FIX

Page Weight Budget

Action

2.4 MB transferred, 32 requests

FIX

2.4 MB transferred, 32 requests

Page weighs 3.5 MB (2.4 MB transferred)

Images are 1.9 MB — compress or use modern formats

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

Got: 1.9 MB

32 HTTP requests

Estimated 0.51 g CO2 per page load

2.4 MB transferred

32 requests

0.51 g CO2 per page load

Images 1.9 MiB 77%

JavaScript 432.5 KiB 17%

Fonts 66.1 KiB 3%

CSS 30.7 KiB 1%

HTML 25.3 KiB 1%

Other 1.5 KiB 0%

Other 551 B 0%

Other 446 B 0%

0 2.4 MB 4.9 MB

Approaching limit

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

Third-Party Impact

Action

100% third-party, 0 ms blocking

FIX

100% third-party, 0 ms blocking

Third-party code accounts for 100% of page weight (2.4 MiB of 2.4 MiB)

Third-party blocking time is low (0 ms)

100%

First-party Third-party

Page Weight Inventory

Action

32 resources · 2.4 MB · 205 KB savings available

FIX

32 resources · 2.4 MB · 205 KB savings available

Page weight 1.4 MB over 1MB target

Got: 2.4 MB Expected: ≤ 1 MB

~205 KB of savings available

31 third-party resources (100% of weight)

2 resources over 200KB

32 resources · 2.4 MiB · 31 third-party 1.4 MiB over 1MB target

Image 78% · 1.9 MiB

JavaScript 17% · 432.5 KiB

Font 3% · 66.1 KiB

CSS 1% · 30.7 KiB

Document 1% · 25.3 KiB

Other 0% · 1.1 KiB

~204.7 KiB of savings available

Remove unused JavaScript: 204.7 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

32 resources			2.4 MiB

HTTP Caching

Action

No cache headers

FIX

No cache headers

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.

Image Optimization

13 images, 0 KB saveable

REVIEW

13 images, 0 KB saveable

https://www.healthdata.org/themes/custom/healthdat... is missing width/height — may cause layout shift

Set explicit width and height to prevent CLS.

13 images 1.9 MB

0 oversized -0 KB

12 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

JS Bundles

Action

9 scripts, 205 KB unused

REVIEW

9 scripts, 205 KB unused

https://www.googletagmanager.com/gtag/js?id=G-0412...: 68 KB unused (44%)