Currency & Crypto API
5 endpoints for fiat and crypto pricing: latest ECB exchange rates for any base currency, fast amount conversion, historical rates back to 1999, single-coin crypto price lookup, and batch crypto pricing for up to 50 coins at once. Per-key TTL cache (1h fiat, 30s crypto) keeps upstream load minimal.
1 of 5 routes settlement-verified · $0.001 USDC/request · 5 endpoints / 5 tools · Data · base network · x402 protocol
Verified routes
/rates/latest· $0.001 · 2026-08-03 · receipt
Other routes are unverified.
Networks: Base (settlement-verified)
Discovery is free. Agents search the catalogue here. Payment happens on the listing 402, not on PayAPI.
url https://payapi.market/mcpReal-time and historical FX rates plus crypto spot prices, for AI agents pricing and converting money.
Endpoints
POST /rates/latest: Latest FX rates for a base currency. ($0.001)POST /rates/convert: Convert an amount between two currencies. ($0.001)POST /rates/historical: Historical FX rates for a date. ($0.001)POST /crypto/price: Spot price for one cryptocurrency. ($0.001)POST /crypto/prices: Spot prices for multiple cryptocurrencies at once. ($0.001)
Example request
curl -X POST https://currency.payapi.market/rates/convert \
-H 'content-type: application/json' \
-d '{"from":"GBP","to":"USD","amount":100}'
Example response
{
"from": "GBP",
"to": "USD",
"amount": 100,
"rate": 1.27,
"result": 127.0,
"as_of": "2026-08-06"
}
How an agent calls this
Convert 100 GBP to USD at today’s rate.
An MCP-connected agent discovers this API, picks it for the task, and pays per call in USDC. No keys, no account.
About this API
Currency & Crypto API is listed in the Data category with pricing at $0.001 USDC/request. One route has been settlement-verified by PayAPI Market on 2026-08-03. View receipt on Basescan.
Payments settle on base in USDC via the x402 protocol. AI agents discover this API through the PayAPI Market MCP server and pay per request without API keys or accounts.
This API exposes 5 endpoints. Only the verified route has been tested by PayAPI Market. Other routes are unverified.
How to call this API
Every protected route returns HTTP 402 with x402 payment requirements. An agent pays the stated USDC amount on Base and retries with the payment header. No API keys, no accounts. Browse the marketplace or list your own API.
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