₿ Bitcoin Fee Heatmap

A GitHub-contribution-style calendar heatmap of Bitcoin transaction fees over the past 365 days. Built as a single static HTML file — no backend, no build step, no dependencies to install.

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Run Locally

# Any static server works
npx serve .
# or
python3 -m http.server 8080

Then open http://localhost:8080

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Data Sources

Data	Endpoint
Historical fee rates	https://mempool.space/api/v1/mining/blocks/fee-rates/all
Current recommended fees	https://mempool.space/api/v1/fees/recommended
BTC price (USD)	https://mempool.space/api/v1/prices
Recent blocks fallback	https://mempool.space/api/v1/blocks

All data is fetched client-side. No server, no API key required.

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Customization

Edit the CSS variables at the top of index.html:

:root {
  --bg:     #0c0c0c;   /* page background */
  --orange: #f7931a;   /* Bitcoin orange accent */
  /* fee heat scale: --c0 (low) through --c6 (high) */
}