BTC Fees API

Current Bitcoin network fee rates and mempool backlog from mempool.space.

Overview

Current Bitcoin network fee rates and mempool backlog from mempool.space. Returns recommended fee rates in satoshis per virtual byte for target confirmation speeds (fastest ~next block, half-hour, hour, economy, minimum) plus the current mempool size (transaction count, total vsize, total fees waiting). Keyless, live. The BTC counterpart to crypto.gas-oracle (Ethereum) — fresh, fast-moving network state an agent cannot recall, for wallets, payment timing, and fee estimation.

Endpoint

Method	Endpoint	Price	Description
GET	/v1/marketplace/api/btc-fees	$0.002875	Invoke Btc Fees (Blockchain) and return the upstream response.

How to call it

Requests are paid per call over the x402 protocol. Call the endpoint, receive a 402 Payment Required quote, then repeat the request with the signed payment header. The SDKs do both steps for you.

# 1. Ask for a quote
curl -i https://jarvisclaw.ai/v1/marketplace/api/btc-fees

# 2. Pay it (the SDK signs and retries for you)
curl -H "X-PAYMENT: <signed-payload>" https://jarvisclaw.ai/v1/marketplace/api/btc-fees

Example response

{
  "data": {
    "ok": true,
    "total": 1,
    "items": [
      {
        "recommendedFeesSatPerVByte": {
          "fastest": 8,
          "halfHour": 6,
          "hour": 4,
          "economy": 2,
          "minimum": 1
        },
        "mempool": {
          "txCount": 42000,
          "vsizeBytes": 18000000,
          "totalFeeSat": 95000000
        },
        "source": {
          "provider": "mempool.space — Bitcoin mempool & fee API",
          "url": "https://mempool.space/docs/api",
          "license": "Open data (MIT-licensed project). Live-wrapped."
        },
        "note": "Recommended fee rates in satoshis per virtual byte for target confirmation speeds, plus current mempool backlog. Live network state; rates move minute to minute."
      }
    ],
    "source": {
      "provider": "mempool.space — Bitcoin mempool & fee API",
      "url": "https://mempool.space/docs/api",
      "license": "Open data (MIT-licensed project). Live-wrapped."
    }
  },
  "meta": {
    "endpoint": "crypto.btc-fees",
    "version": null,
    "caller": "x402",
    "cost": {
      "usd": 0.0025
    },
    "settlement": {
      "txHash": "[redacted]",
      "network": "eip155:8453",
      "success": true
    }
  }
}

FAQ

How much does the Btc Fees API cost?

$0.002875 USDC per call, paid per call over x402. There is no subscription, minimum or monthly fee.

Do I need an API key?

No. Call the endpoint, read the 402 Payment Required quote, and repeat the request with a signed USDC payment header. An account API key also works if you prefer prepaid billing.

Which chains can I pay on?

USDC on Base or on Solana. The 402 quote lists the accepted networks and the exact amount; the JarvisClaw SDKs sign and retry for you.

How do I call it from an AI agent?

Send GET to the endpoint above from any HTTP client, or connect the JarvisClaw MCP server and let the agent find and call it with the search_apis and get_api_detail tools.

Related APIs

• Crypto Markets
• Crypto News Api
• Address Screen
• Defi Analytics
• Crypto Defi

Open in the marketplace