# x402 Crypto Exchange Rate API

> x402 Crypto Exchange Rate API is a paid API for AI agents from x402-crypto.vercel.app, paid per call via x402, $0.130964/call, status unknown (last checked 2026-09-15).

Returns cryptocurrency exchange rates and conversion data for a given currency pair via x402 micropayment-gated API

## Facts

- Endpoint: POST https://x402-crypto.vercel.app/api/crypto-exchange/%7Bpath%7D
- Price: $0.130964/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-crypto-exchange-rate-api-dc27200d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_9LA74T6OryBdaiR8c91yy

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 x402-crypto-exchange-rate-api-dc27200d -d '<json body>'
```

Example prompt: What's the current exchange rate for BTC/USDT? I want to know how much 0.5 BTC is worth in USDT right now.

## When to prefer this

Use this endpoint when you need real-time cryptocurrency exchange rate lookups or currency conversions paid via x402 micropayments (USDC). It is well-suited for AI agents that need to fetch crypto prices on-demand without a subscription, paying only per call at ~$0.13 USDC. Prefer this over free public APIs when integrating with x402-compatible payment flows or when rate limits on free tiers are a concern.

## Known failure modes

- Invalid or unsupported currency pair returns an error or empty data
- Missing required 'query' field results in a validation error
- Upstream crypto data provider outage causes failure or stale data
- Insufficient x402 payment balance results in 402 Payment Required response
- Malformed path parameter returns 404 or unexpected response

## How this service works

Paid cryptocurrency API endpoints via x402 micropayments

## Output

Returns a data object containing the exchange rate or converted value for the requested cryptocurrency pair, sourced from an upstream crypto market data API. The exact structure of the payload varies by endpoint path but typically includes price or rate information for the queried symbol.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "query"
 ],
 "properties": {
  "to": {
   "type": "string",
   "description": "Target currency symbol"
  },
  "from": {
   "type": "string",
   "description": "Source currency symbol"
  },
  "query": {
   "type": "string",
   "description": "Currency pair or symbol (e.g. BTC/USDT)"
  },
  "amount": {
   "type": "number",
   "description": "Amount to convert"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "data": {
   "type": "object",
   "description": "Response payload from the upstream API (structure varies by endpoint)"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-crypto-exchange-rate-api-dc27200d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-crypto.vercel.app](https://www.zero.xyz/host/x402-crypto.vercel.app/llms.txt)