https://simpleswap.io/?id=jvw7l9dn7nk6aj4j

Performance

· 23 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.

781 ms

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

1.66 s

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

91 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.

1.70 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.

1.88 s

Page Load Progression

672 ms

1.3 s

2.0 s

2.7 s

3.4 s

4.0 s

4.7 s

5.4 s

Checks

10 PASS 7 REVIEW 2 FIX

Third-Party Impact

Action

75% third-party, 0 ms blocking

FIX

75% third-party, 0 ms blocking

Third-party code accounts for 75% of page weight (819.0 KiB of 1.1 MiB)

Third-party blocking time is low (0 ms)

25%

75%

First-party Third-party

HTTP Caching

Action

no-store (uncacheable)

FIX

no-store (uncacheable)

Cache-Control: no-store prevents all caching

Intentional for dynamic content, but increases server load for every page view.

Got: private, no-cache, no-store, max-age=0, must-revalidate

No ETag or Last-Modified header

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

Cache-Control

private, no-cache, no-store, max-age=0, must-revalidate

Directive	Value	Meaning
private	—	Only browser cache, not CDN/proxy
no-cache	—	Cache but always revalidate first
no-store	—	Never cache this response
max-age	0	Cache for 0 seconds
must-revalidate	—	Must recheck with server after expiry

Page Weight Budget

1.1 MB transferred, 77 requests

REVIEW

1.1 MB transferred, 77 requests

Page weighs 3.4 MB (1.1 MB transferred)

77 HTTP requests

Estimated 0.22 g CO2 per page load

1.1 MB transferred

77 requests

0.22 g CO2 per page load

JavaScript 397.8 KiB 36%

Images 340.0 KiB 31%

HTML 262.2 KiB 24%

Fonts 78.7 KiB 7%

Other 12.5 KiB 1%

Other 3.9 KiB 0%

Other 2.5 KiB 0%

Other 153 B 0%

0 2.4 MB 4.9 MB

Under budget

Image Optimization

29 images, 0 KB saveable

REVIEW

29 images, 0 KB saveable

All images are well-optimized

29 images 340 KB

0 oversized -0 KB

23 legacy format

0 missing dimensions CLS risk

JS Execution Cost

Action

1810ms total JS execution

REVIEW

1810ms total JS execution

https://simpleswap.io/?id=jvw7l9dn7nk6aj4j: 842ms CPU time

https://edge.simpleswap.io/exchange-frontend/stati...: 516ms CPU time

Unattributable: 377ms CPU time

https://edge.simpleswap.io/exchange-frontend/stati...: 75ms CPU time

Third-party scripts: 591ms (33% of total)

Main Thread Breakdown

Other 42% Script Evaluation 32% Style & Layout 10% Script Parsing & Compilation 5% Parse HTML & CSS 5% Rendering 5%

Script	Total	Scripting	Parse/Compile	Party
https://simpleswap.io/?id=jvw7l9dn7nk6aj4j	842ms	21ms	50ms	1st
https://edge.simpleswap.io/exchange-frontend/static/_next/static/chunks/10rj~6lwyv6l~.js	516ms	478ms	8ms	3rd
Unattributable	377ms	12ms	0ms	1st
https://edge.simpleswap.io/exchange-frontend/static/_next/static/chunks/0rs9-y4l1po~a.js	75ms	69ms	3ms	3rd

HTTP/3 (QUIC)

HTTP/3 not advertised

REVIEW

HTTP/3 not advertised

HTTP/3 (QUIC) is not advertised

HTTP/3 isn't advertised via Alt-Svc and the worker didn't negotiate h3. HTTP/3 reduces handshake latency (1-RTT instead of 2-3 RTTs) and is more resilient on lossy connections. Most modern CDNs (Cloudflare, Fastly, AWS CloudFront, Google Cloud CDN) support HTTP/3 with a single config switch -- consider enabling for mobile-heavy workloads.

Compression Algorithm

Main response uses gzip; brotli would be ~20% smaller

REVIEW

Main response uses gzip; brotli would be ~20% smaller

Main HTML response uses gzip (brotli would be ~20% smaller)

All current browsers support brotli. Most CDNs (Cloudflare, Fastly, AWS CloudFront, Vercel, Netlify) can switch from gzip to brotli with a single config flag. Origin servers (nginx, Apache) need a brotli module compiled in -- nginx-brotli or Apache mod_brotli.

Server-Timing Observability

No Server-Timing header found

REVIEW

No Server-Timing header found

Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.

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

All text resources are properly compressed.

A+

Font Loading

5 fonts (79 KB)

PASS

5 fonts (79 KB)

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

Web fonts

79 KB total

Render-blocking

of 5

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

47fe1b7cd6e6ed85.p.0~mc... woff2 swap

Size 8 KB

Load time 711 ms

Start 853 ms