Bitcoin fee rates and mempool status
Current Bitcoin network fee rates in sat/vB for next-block, half-hour, one-hour and economy confirmation, the estimated cost in sats of a typical payment, mempool size and total pending fees, and the latest block height. Use before sending a Bitcoin transaction or to decide whether to wait for lower fees.
Request
Over HTTP, with a card key from /credits:
curl -H "Authorization: Bearer adt_…" "https://agent-data-tools.revmesh2074.workers.dev/btc-fees?format=json"
Or one of your 25 free calls, no key:
curl "https://agent-data-tools.revmesh2074.workers.dev/btc-fees?format=json&trial=1"
Without a key, the same URL answers 402 Payment Required with x402 and MPP terms, so an agent with a wallet pays per call in USDC (Base, Polygon, Arbitrum, Monad, World Chain or Tempo) and retries.
Example result
{
"network": "bitcoin",
"unit": "sat/vB",
"fees": {
"nextBlock": 4,
"halfHour": 3,
"hour": 1,
"economy": 1,
"minimum": 1
},
"typicalPaymentSats": {
"nextBlock": 564,
"hour": 141
},
"typicalPaymentVbytes": 141,
"source": "https://mempool.space/api",
"limitations": [
"Estimates do not guarantee confirmation time",
"141 vB is an illustrative one-input/two-output SegWit size; actual transaction size varies",
"Source endpoints are fetched concurrently, not as an atomic snapshot"
],
"mempool": {
"transactions": 83832,
"vsize": 42066150,
"totalFeesBtc": 0.1093664
},
"blockHeight": 970000,
"checkedAt": "2026-10-01T00:00:00.000Z"
}
From an AI agent (MCP)
Add the MCP server to Claude, Cursor or any MCP client. This tool is btc_fees, and the first 25 successful calls are free:
https://agent-data-tools.revmesh2074.workers.dev/mcp