API Reference

Exchange rate endpoints

Customer API endpoints use /v2 and require an API key. Legacy /v1 endpoints remain available for the browser extension compatibility path.

Authentication

Send an API key with every /v2 customer API request.

X-API-Key: cp_live_xxx

Authorization: Bearer cp_live_xxx

Legacy /v1 requests without an API key are still allowed for extension compatibility.

Optional client headers can identify public extension traffic for analytics only.

X-Client: extension
X-Client-Version: 1.2.3

Fiat rates

GET /v2/exchange

{
  "code": 200,
  "base": "USD",
  "data": [...],
  "TimeLastUpdate": "2026-05-18 08:02:31",
  "TimeLastGet": "2026-05-18 12:20:05"
}

Crypto rates

Free API keys receive the core crypto whitelist. Paid plans receive all enabled crypto assets. Legacy /v1 requests remain compatible for the extension.

GET /v2/exchange_crypto

{
  "code": 200,
  "base": "USDT",
  "data": [...],
  "periodInMinutes_crypto": 3
}

Errors

401 missing, invalid, or disabled API key
403 disabled customer, disabled plan, or plan does not allow this endpoint
429 quota exceeded