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FastX402 Lab BTC Fees
x402
FastX402 Lab BTC Fees is a paid API for AI agents from lab.fastx402.tools, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-17).
Returns current Bitcoin mempool fee rates and mempool statistics for a given network (mainnet, testnet3, or testnet4)
Price / call$0.003
Success—
StatusUnknown
How this service works
FastX402 Lab: small pay-per-call tools for AI agents, paid per request in USDC on Base over x402. No signup, no API key.
Output
A JSON object containing the queried network name, fee rates in sat/vbyte for four confirmation targets (economy, one_hour, thirty_minutes, fastest), and mempool statistics including total virtual size in bytes, transaction count, and total fees in satoshis.
Example use cases
Optimize BTC transaction fee before sending
“I'm about to send a Bitcoin transaction — what's the current fastest and economy fee rate in sat/vb on mainnet so I can decide how much to pay?”
Monitor mempool congestion for trading bot
“Check the Bitcoin mainnet mempool right now — how many pending transactions are there and what's the total fee in satoshis? I want to know if it's congested.”
Set testnet fee for developer testing
“I'm testing a Bitcoin app on testnet4 — what fee rate should I use to get confirmed in about 30 minutes?”
Technical details
Endpoint
GEThttps://lab.fastx402.tools/btc-fees?utm_source=zero.xyzWhen to prefer
Choose this endpoint when an AI agent needs real-time Bitcoin fee estimates to set transaction fees or assess mempool congestion, especially in a pay-per-call context where no API key or signup is desired. It is well-suited for lightweight, infrequent fee lookups paid in USDC on Base via x402.
Side effects
- Invalid network value returns an error (valid values: main, testnet3, testnet4)
- Network or upstream mempool data unavailable returns a server error
- Payment failure or insufficient USDC balance prevents call from completing
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"mempool": {
"vsize": 30000000,
"transactions": 5000,
"total_fee_sat": 61234567
},
"network": "main",
"fee_rates_sat_vb": {
"economy": 10,
"fastest": 20,
"one_hour": 15,
"thirty_minutes": 17
}
}
}Tags
x402
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