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

100

Best Practices

100

SEO

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

1.36 s

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

2.76 s

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

84 ms

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

0.007

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

1.43 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.

2.80 s

Page Load Progression

600 ms

1.2 s

1.8 s

2.4 s

3.0 s

3.6 s

4.2 s

4.8 s

Checks

8 PASS 4 REVIEW 1 FIX

Third-Party Impact

Action

97% third-party, 0 ms blocking

FIX

97% third-party, 0 ms blocking

Third-party code accounts for 97% of page weight (972.8 KiB of 1001.9 KiB)

Third-party blocking time is low (0 ms)

97%

First-party Third-party

Image Optimization

26 images, 0 KB saveable

REVIEW

26 images, 0 KB saveable

All images are well-optimized

26 images 406 KB

0 oversized -0 KB

10 legacy format

0 missing dimensions CLS risk

JS Execution Cost

Action

1170ms total JS execution

REVIEW

1170ms total JS execution

https://ixdf.org/: 369ms CPU time

https://t.ixdf.org/gtag/js?id=G-WP2YP70Z2X&cx=c&gt...: 267ms CPU time

Unattributable: 234ms CPU time

https://assets.interaction-design.org/build/assets...: 177ms CPU time

https://t.ixdf.org/gtm.js?id=GTM-KJ8XGB: 122ms CPU time

Third-party scripts: 801ms (68% of total)

Main Thread Breakdown

Script Evaluation 37% Other 32% Style & Layout 16% Rendering 7% Script Parsing & Compilation 4% Parse HTML & CSS 3%

Script	Total	Scripting	Parse/Compile	Party
https://ixdf.org/	369ms	8ms	2ms	1st
https://t.ixdf.org/gtag/js?id=G-WP2YP70Z2X&cx=c&gtm=4e64k1	267ms	227ms	23ms	3rd
Unattributable	234ms	12ms	0ms	3rd
https://assets.interaction-design.org/build/assets/bugsnag-1RJHgweM.js	177ms	56ms	0ms	3rd
https://t.ixdf.org/gtm.js?id=GTM-KJ8XGB	122ms	101ms	19ms	3rd

JS Bundles

46 scripts, 118 KB unused

REVIEW

46 scripts, 118 KB unused

https://t.ixdf.org/gtag/js?id=G-WP2YP70Z2X&cx=c&gt...: 60 KB unused (35%)

Consider code splitting or tree shaking to reduce unused code.

https://t.ixdf.org/gtm.js?id=GTM-KJ8XGB: 58 KB unused (37%)

Consider code splitting or tree shaking to reduce unused code.

Total unused JavaScript: 118 KB

118 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://t.ixdf.org/gtag/js?id=G-WP2YP70Z2X&cx=c&gtm=4e64k1	171 KB	60 KB (35%)	✓	3rd
https://t.ixdf.org/gtm.js?id=GTM-KJ8XGB	156 KB	58 KB (37%)	✓	3rd
https://assets.interaction-design.org/build/assets/course-DfCRK5qh.js	1 KB	—	✓	3rd
https://assets.interaction-design.org/build/assets/button-DU36gPX9.js	2 KB	—	✓	3rd
https://assets.interaction-design.org/build/assets/notification-f2Rm4oS7.js	2 KB	—	✓	3rd
https://assets.interaction-design.org/build/assets/spinner--AwVl_E8.js	1 KB	—	✓	3rd
https://assets.interaction-design.org/build/assets/auth-S67ULf_r.js	1 KB	—	✓	3rd
https://assets.interaction-design.org/build/assets/cookie-RmvTIN1d.js	1 KB	—	✓	3rd
https://assets.interaction-design.org/build/assets/smoothAnchor-Bdh_NRTq.js	1 KB	—	✓	3rd
https://assets.interaction-design.org/build/assets/cssVariables-Bz9wRQEm.js	1 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

HTTP Caching

no-cache, private

REVIEW

no-cache, private

Cache-Control header is set

Got: no-cache, private

No ETag or Last-Modified header

Conditional requests (304 Not Modified) are not possible without validators.

Cache-Control

no-cache, private

Directive	Value	Meaning
no-cache	—	Cache but always revalidate first
private	—	Only browser cache, not CDN/proxy

Page Weight Budget

1002 KB transferred, 85 requests

PASS

1002 KB transferred, 85 requests

Page weighs 2.8 MB (1002 KB transferred)

85 HTTP requests

Estimated 0.21 g CO2 per page load

1002 KB transferred

85 requests

0.21 g CO2 per page load

JavaScript 426.5 KiB 43%

Images 405.8 KiB 41%

CSS 53.7 KiB 5%

Fonts 42.7 KiB 4%

Other 39.1 KiB 4%

HTML 30.9 KiB 3%

Other 3.0 KiB 0%

Other 88 B 0%

Other 0 B 0%

0 2.4 MB 4.9 MB

Under budget

A+

Text Compression

All text resources are compressed

PASS

All text resources are compressed

All text resources are properly compressed.

A+

Font Loading

2 fonts (43 KB)

PASS

2 fonts (43 KB)

2 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

43 KB total

Render-blocking

of 2

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

arimo-normal-latin-CtqM... woff2 swap

Size 20 KB

Load time 449 ms

Start 180 ms

Risk FOUT — text flashes from fallback to web font

arimo-italic-latin-CEN6... woff2 swap

Size 22 KB

Load time 18 ms

Start 744 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

No caching issues found

All static resources have appropriate caching headers.

A+

Critical Rendering Path

No render-blocking resources

PASS

No render-blocking resources

No render-blocking resources detected

A+

Resource Hints

No optimization needed

PASS

No optimization needed

No resource hint issues

Page Weight Inventory

85 resources · 1002 KB · 118 KB savings available

PASS

85 resources · 1002 KB · 118 KB savings available

Within 1MB page-weight target

Got: 1002 KB

~118 KB of savings available

84 third-party resources (97% of weight)

85 resources · 1001.9 KiB · 84 third-party Within 1MB page-weight target

Image 45% · 447.2 KiB

JavaScript 43% · 426.5 KiB

CSS 5% · 53.7 KiB

Font 4% · 42.7 KiB

Document 3% · 30.9 KiB

Other 0% · 877 B

~118.2 KiB of savings available

Remove unused JavaScript: 118.2 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

85 resources			1001.9 KiB

A+

Green Hosting

Whether the site is served from green-energy infrastructure

PASS

Green Hosting

This site is hosted on green energy infrastructure

Provider: Cloudflare

Network Waterfall

85 requests over 2540ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Third-Party Script Cost

Per-script blocking time, transfer cost, and cache headers

INFO

68% of JavaScript execution is third-party

First-party Third-party 801ms · 343KB · $11/mo

Script	Category	Execution	Transfer	Unused	Monthly Cost	Verdict
t.ixdf.org t.ixdf.org	Other	267ms	171 KB	35%	$4/mo	Costly
Unattributable Unattributable	Other	234ms	0 KB	—	$3/mo	Costly
assets.interaction-design.org assets.interaction-design.org	Other	177ms	16 KB	—	$2/mo	Optional
t.ixdf.org t.ixdf.org	Other	122ms	156 KB	37%	$2/mo	Optional

t.ixdf.org

Other

Costly

Execution 267ms

Transfer 171 KB

Unused 35%

Monthly Cost $4/mo

Unattributable

Other

Costly

Execution 234ms

Transfer 0 KB

Monthly Cost $3/mo

assets.interaction-design.org

Other

Optional

Execution 177ms

Transfer 16 KB

Monthly Cost $2/mo

t.ixdf.org

Other

Optional

Execution 122ms

Transfer 156 KB

Unused 37%

Monthly Cost $2/mo

These scripts may cost more than they're worth

t.ixdf.org adds 267ms and costs ~$4/month
Unattributable adds 234ms and costs ~$3/month

68% of JavaScript execution time comes from third-party scripts.

Why this matters

Third-party scripts (analytics, ads, social, A/B testing) often dominate execution time — every one is a perf-and-privacy tax.

Learn more ▾

Each third-party script is a black box: you don't control when it loads, what it executes, or how much it grows. They often account for a major share of total blocking time on average sites (HTTP Archive's Web Almanac documents the trend). Audit which ones you actually need, defer the rest, and use facade patterns (lite-youtube, lite-vimeo) for embedded media.

Source: web.dev / HTTP Archive Web Almanac

t.ixdf.org takes 267ms 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 234ms 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.