Performance

· 26 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.

2.79 s

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

4.27 s

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

117 ms

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

0.001

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

3.65 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.

4.27 s

Page Load Progression

479 ms

958 ms

1.4 s

1.9 s

2.4 s

2.9 s

3.4 s

3.8 s

Checks

14 PASS 6 REVIEW 3 FIX

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 (1.9 MiB of 1.9 MiB)

Third-party blocking time is low (0 ms)

100%

First-party Third-party

Page Weight Inventory

Action

126 resources · 1.9 MB · 26 KB savings available

FIX

126 resources · 1.9 MB · 26 KB savings available

Page weight 1.9 MB exceeds 1 MB target by 949 KB

Got: 1.9 MB Expected: ≤ 1 MB

125 third-party resources (100% of weight)

1 resources over 200KB

126 resources · 1.9 MiB · 125 third-party 948.6 KiB over 1MB target

Image 77% · 1.5 MiB

Media 12% · 235.6 KiB

JavaScript 5% · 100.7 KiB

Font 2% · 47.3 KiB

Document 2% · 35.1 KiB

CSS 1% · 25.6 KiB

Other 0% · 1.2 KiB

~26.1 KiB of savings available

Remove unused JavaScript: 26.1 KiB

#	Resource	Type	Size	Cache	Unused	3rd party	Issues

126 resources			1.9 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.

Page Weight Budget

Action

1.9 MB transferred, 126 requests

REVIEW

1.9 MB transferred, 126 requests

Page weighs 2.7 MB (1.9 MB transferred)

Images are 1.5 MB — compress or use modern formats

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

Got: 1.5 MB

126 HTTP requests — consider bundling or reducing

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Estimated 0.40 g CO2 per page load

1.9 MB transferred

126 requests

0.40 g CO2 per page load

Images 1.5 MiB 76%

Other 235.6 KiB 12%

JavaScript 100.7 KiB 5%

Fonts 47.3 KiB 2%

HTML 34.9 KiB 2%

Other 34.3 KiB 2%

CSS 25.6 KiB 1%

Other 573 B 0%

Other 424 B 0%

Other 196 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

Each request adds latency. Bundle small files, use sprites, or eliminate unnecessary requests.

Why this matters

High HTTP request count — bundling, sprite-ing, and HTTP/2 server push can reduce per-request overhead.

Source: web.dev

Image Optimization

104 images, 0 KB saveable

REVIEW

104 images, 0 KB saveable

All images are well-optimized

104 images 1.5 MB

0 oversized -0 KB

31 legacy format

0 missing dimensions CLS risk

JS Execution Cost

Action

1894ms total JS execution

REVIEW

1894ms total JS execution

https://www.bang.com/build/8683.20825f0f.js: 722ms CPU time

Unattributable: 544ms CPU time

https://www.bang.com/: 418ms CPU time

https://www.bang.com/build/5583.9aaae509.js: 209ms CPU time

Third-party scripts: 1350ms (71% of total)

Main Thread Breakdown

Other 40% Script Evaluation 26% Style & Layout 23% Rendering 6% Parse HTML & CSS 4%

Script	Total	Scripting	Parse/Compile	Party
https://www.bang.com/build/8683.20825f0f.js	722ms	224ms	5ms	3rd
Unattributable	544ms	22ms	0ms	1st
https://www.bang.com/	418ms	31ms	3ms	3rd
https://www.bang.com/build/5583.9aaae509.js	209ms	156ms	13ms	3rd

Compression Algorithm

Action

Main response served uncompressed

REVIEW

Main response served uncompressed

Main HTML response has no Content-Encoding (uncompressed)

The main HTML document is served without compression. The Text Compression section above lists the broader picture; for the main response specifically, even gzip would shave ~70-80% off most text payloads.

Main HTML Cache-Control

No Cache-Control header on main HTML response

REVIEW

No Cache-Control header on main HTML response

Main HTML response has no Cache-Control header

Without an explicit Cache-Control, browsers fall back to heuristic caching (~10% of Last-Modified age). Set `Cache-Control: no-cache` or `max-age=300` for HTML to control freshness explicitly -- prevents stale auth state and SPA shell drift.

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.

A+

Text Compression

All text resources are compressed

PASS

All text resources are compressed

All text resources are properly compressed.

A+

Font Loading

1 fonts (47 KB)

PASS

1 fonts (47 KB)

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

Web fonts

47 KB total

Render-blocking

of 1

Dominant font-display

swap

Most common across fonts

Font loading timeline

Transfer FOIT (block) FOUT (swap)

inter-latin-wght-normal... woff2 swap

Size 47 KB

Load time 43 ms

Start 291 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+

JS Bundles

11 scripts, 26 KB unused

PASS

11 scripts, 26 KB unused

https://www.bang.com/build/5583.9aaae509.js: 26 KB unused (68%)

Consider code splitting or tree shaking to reduce unused code.

Total unused JavaScript: 26 KB

26 KB unused JavaScript

Downloaded but never executed on this page.

Script	Size	Unused	Minified	Party
https://www.bang.com/build/5583.9aaae509.js	39 KB	26 KB (68%)	✓	3rd
https://www.bang.com/build/runtime.68aceb16.js	2 KB	—	✓	3rd
https://www.bang.com/build/app.61795e1d.js	20 KB	—	✓	3rd
https://static.cloudflareinsights.com/beacon.min.js/v4513226cdae34746b4dedf0b4dfa099e1781791509496	11 KB	—	✓	3rd
https://www.bang.com/build/2508.c1088495.js	1 KB	—	✓	3rd
https://www.bang.com/build/6397.da151aba.js	1 KB	—	✓	3rd
https://www.bang.com/build/8159.b9d5cfc4.js	1 KB	—	✓	3rd
https://www.bang.com/build/3247.887588e4.js	1 KB	—	✓	3rd
https://www.bang.com/build/8683.20825f0f.js	24 KB	—	✓	3rd
https://www.bang.com/build/6618.afa35acc.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

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

2 hints, 0 missing preconnects

PASS

2 hints, 0 missing preconnects

Page uses 2 resource hint(s)

Current Resource Hints

preconnect

preload

dns-prefetch

—

prefetch

—

2 resource hints configured

A+

HTTP/3 (QUIC)

HTTP/3 advertised via Alt-Svc

PASS

HTTP/3 advertised via Alt-Svc

HTTP/3 (QUIC) is supported

First-load mobile users on cellular networks see meaningful latency improvements with HTTP/3. The QUIC transport collapses TLS + TCP handshakes into one and recovers faster from packet loss.

A+

LCP Image Preload

LCP preload audit not available

PASS

LCP preload audit not available

LCP image preload audit not available for this scan

A+

Server Response Intelligence

1 server-response signal(s) detected

PASS

1 server-response signal(s) detected

No `ETag` or `Last-Modified` -- conditional GET not supported

Without either header, browsers can't issue conditional GETs and refresh always re-downloads the full response body even when nothing changed. Add `ETag: "<hash>"` (or `Last-Modified: <date>`) on cacheable responses; the server returns 304 Not Modified when the client's cached copy is still valid, saving bandwidth.

A+

Render-Blocking Resources

No render-blocking resources detected

PASS

No render-blocking resources detected

No render-blocking resources detected in <head>

A+

Third-Party Resources

No third-party resources detected

PASS

No third-party resources detected

A+

JavaScript Blocking

No render-blocking JS or document.write usage detected

PASS

No render-blocking JS or document.write usage detected

No JavaScript blocking issues detected

A+

CSS Performance Depth

No CSS performance depth issues detected

PASS

No CSS performance depth issues detected

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

126 requests over 2835ms

INFO

HTML JavaScript CSS Images Fonts XHR/Fetch Other

Third-Party Script Cost

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

INFO

71% of JavaScript execution is third-party

First-party Third-party 1350ms · 97KB · €15/mo

Script	Category	Execution	Transfer	Unused	Monthly Cost	Verdict
www.bang.com www.bang.com	Other	722ms	24 KB	—	€8/mo	Costly
www.bang.com www.bang.com	Other	418ms	35 KB	—	€5/mo	Costly
www.bang.com www.bang.com	Other	209ms	39 KB	68%	€2/mo	Costly

www.bang.com

Other

Costly

Execution 722ms

Transfer 24 KB

Monthly Cost €8/mo

www.bang.com

Other

Costly

Execution 418ms

Transfer 35 KB

Monthly Cost €5/mo

www.bang.com

Other

Costly

Execution 209ms

Transfer 39 KB

Unused 68%

Monthly Cost €2/mo

These scripts may cost more than they're worth

www.bang.com adds 722ms and costs ~€8/month
www.bang.com adds 418ms and costs ~€5/month
www.bang.com adds 209ms and costs ~€2/month

71% 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.bang.com takes 722ms 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

www.bang.com takes 418ms 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

www.bang.com takes 209ms 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

68% of www.bang.com's code is unused. The script may be loading features you don't use.

Why this matters

Bundle has high unused-code ratio — tree-shaking and route-splitting recover the wasted bytes.

Source: web.dev

How third-party costs are calculated

Image Optimization

129 images, 0 KB total, 0 KB wasted

INFO

Image Optimization Audit

Total Images

129

Total Size

0 KB

8 missing lazy loading

All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.