# Bitcoin Fee Rate Estimates API

> Bitcoin Fee Rate Estimates API is a paid API for AI agents from api.relai.fi, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-15).

Returns current Bitcoin network fee rate estimates for transaction fee planning

## Facts

- Endpoint: GET https://api.relai.fi/relay/1780781322365/api/fees
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/bitcoin-fee-rate-estimates-api-0f3ef96b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OWxkzREIImHvxO1fKDjQk

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability bitcoin-fee-rate-estimates-api-0f3ef96b
```

Example prompt: What are the current Bitcoin fee rates — like how many sats per byte should I use if I want a fast confirmation versus a slow one?

## When to prefer this

Use this endpoint when you need real-time Bitcoin fee rate estimates to set appropriate miner fees for transactions, particularly when you need tiered fee recommendations (fast, medium, slow) without running your own Bitcoin node. Ideal for wallets, payment processors, or automation scripts that need current mempool-based fee guidance.

## Known failure modes

- Bitcoin node unavailable or syncing — returns 5xx error
- Relay infrastructure timeout — returns gateway error
- Rate limiting or payment issue — returns 402 or 429
- Empty or stale fee data if mempool is not fully synced

## How this service works

Bitcoin fee rate estimates

## Output

Returns current Bitcoin fee rate estimates, typically including tiers such as fastest, half-hour, and one-hour confirmation targets expressed in satoshis per byte or satoshis per virtual byte (sat/vbyte).

## Example request

```json
{
 "input": {
  "type": "http",
  "method": "GET",
  "queryParams": {}
 }
}
```

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/bitcoin-fee-rate-estimates-api-0f3ef96b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.relai.fi](https://www.zero.xyz/host/api.relai.fi/llms.txt)