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Real-time and historical FX conversion for developers

Currency API

The Currency API delivers accurate, key-free foreign-exchange conversion and exchange rates backed by official European Central Bank reference data (via Frankfurter), with an automatic secondary provider fallback so your application keeps working even when an upstream hiccups.

Convert any amount between 30+ major currencies, pull live or historical rates, and list every supported currency from a single clean JSON interface. Built on a global edge network, it answers in milliseconds with intelligently cached responses, making it ideal for e-commerce pricing, expense tracking, fintech dashboards, and back-office reconciliation.

Free tier included, no credit card required. One key works across all 49 APIs.

At a glance
Currencies
30+
Response Time
<50ms
Uptime SLA
99.9%

Key features

  • Real-time currency conversion between any two currencies
  • Latest exchange rates for any base currency
  • Historical conversion using rates from a specific date
  • Directory of all supported currency codes and names
  • ECB-backed reference data with automatic provider fallback
  • Edge-cached JSON responses for low latency worldwide
  • No upstream API keys, scraping, or surprise rate limits

Built for

  • E-commerce multi-currency pricing and checkout
  • Expense tracking and receipt normalization
  • Fintech and trading dashboards
  • Back-office reconciliation and accounting
  • Travel and booking platforms
  • Invoicing in customers’ local currencies
  • Financial reporting and analytics
  • Cross-border payment estimates

Try it

Build the request for your data

Edit the parameters below and see the exact curl command and JSON response you will get. No key required to preview.

GET/currency/v1/convert
Open in Playground

Parameters

Request · HTTP
GET /currency/v1/convert?from=USD&to=EUR&amount=100&apikey=YOUR_KEY HTTP/1.1
Host: api.apicodex.io
Response · JSON
200 OK
{
"from": "USD",
"to": "EUR",
"amount": 100,
"rate": 0.86081,
"result": 86.081,
"date": "2026-05-28",
"source": "frankfurter"
}

Documentation

Currency API Documentation

The Currency API provides real-time and historical foreign-exchange rates and currency conversion, backed by the European Central Bank (via Frankfurter) with an automatic open.er-api fallback. It exposes four endpoints: convert, latest rates, historical conversion, and a supported-currencies directory.

Base URL

url
https://api.apicodex.io

Authentication

Authenticate your requests by appending your API key as a query parameter:

headers
https://api.apicodex.io/currency/v1/convert?from=USD&to=EUR&amount=100&apikey=YOUR_KEY

Request and response

Illustrative values. Confirm current endpoint behavior, quotas, and data freshness in the API documentation before production use.

request · http
GET /currency/v1/convert?from=USD&to=EUR&amount=100&apikey=YOUR_KEY HTTP/1.1
response · json
{
"from": "USD",
"to": "EUR",
"amount": 100,
"rate": 0.86081,
"result": 86.081,
"date": "2026-05-28",
"source": "frankfurter"
}

Code examples

cURL
curl --request GET \
  --url 'https://api.apicodex.io/currency/v1/convert?from=USD&to=EUR&amount=100&apikey=YOUR_KEY'

Endpoints

GET /currency/v1/convert

Convert an amount between two currencies using the latest rates.

/currency/v1/convert?from=USD&to=EUR&amount=100&apikey=YOUR_KEY

GET /currency/v1/rates

Get the latest exchange rates for a base currency, optionally filtered by symbols.

/currency/v1/rates?base=USD&symbols=EUR,GBP,JPY&apikey=YOUR_KEY

GET /currency/v1/historical

Convert an amount using exchange rates from a specific past date.

/currency/v1/historical?date=2024-01-15&from=USD&to=EUR&amount=100&apikey=YOUR_KEY

GET /currency/v1/currencies

List all supported currency codes and their names.

/currency/v1/currencies?apikey=YOUR_KEY

Query Parameters

Required parameters

  • from Source 3-letter currency code (e.g. USD). Required for /convert and /historical.
  • to Target 3-letter currency code (e.g. EUR). Required for /convert and /historical.
  • date Historical date in YYYY-MM-DD format. Required for /historical.

Optional parameters

  • amount Amount to convert. Defaults to 1. Used by /convert and /historical.
  • base Base 3-letter currency code for /rates. Defaults to EUR.
  • symbols Comma-separated list of target currency codes for /rates. Returns all currencies if omitted.
  • apikey Your API key, passed as a query parameter on every request.

Pricing

Currency API Pricing

One key, one subscription, all 49 APIs. Start free and upgrade when you grow. No minimums, no lock-in.

This API costs 5 credits per request. Credits are shared across every API on your plan.

Estimate your monthly cost

Drag the slider to match your expected request volume. We will recommend the cheapest plan that covers it.

10,000

Recommended plan

Starter

$29.99 /month

Credits used50,000
Credits included50,000
Cost per 1K requests$2.999
Choose Starter

Free

Free
1,000 credits · ~200 requests/mo · 2 rps
  • All 49 APIs included
  • No credit card required
  • Full documentation and examples
Start for free

Starter

Popular
$29.99/month
50,000 credits · ~10,000 requests/mo · 10 rps
  • All 49 APIs included
  • Email support
  • Usage dashboard and analytics
Start with Starter

Pro

$99.99/month
250,000 credits · ~50,000 requests/mo · 25 rps
  • All 49 APIs included
  • Priority support
  • Up to 5 API keys
Start with Pro

Need a different plan?

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Coming soon · MCP

Use the Currency API from your AI agent

The API Codex MCP server will expose this API, and the other 39, to Claude, Cursor and any MCP client as tools. Same key, same credits, one config entry.

About the MCP server

FAQ

Frequently asked questions

Exchange rates are sourced from official European Central Bank reference data, delivered via the Frankfurter dataset. If the primary source is temporarily unavailable, the API automatically falls back to a secondary provider (open.er-api) so your application keeps working. Every response includes a 'source' field indicating which provider served the data.

The API supports 30+ major world currencies, including USD, EUR, GBP, JPY, and more. You can retrieve the complete, up-to-date list of supported currency codes and their human-readable names at any time by calling the /currency/v1/currencies endpoint, which also returns a count of available currencies.

Yes. The /currency/v1/historical endpoint lets you convert an amount using the exchange rates that were in effect on a specific past date. Simply pass a date in YYYY-MM-DD format along with the from and to currency codes and an optional amount. This is ideal for reconciling transactions, generating accurate historical reports, and auditing.

The underlying European Central Bank reference rates are published once per business day. Because rates do not change minute-to-minute, you generally only need to refresh a given currency pair once per hour at most. We recommend caching responses on your side and using the 'date' field in the response to decide when a refresh is needed.

Authentication is handled with a single API key passed as a query parameter. Append &apikey=YOUR_KEY to any request, for example /currency/v1/convert?from=USD&to=EUR&amount=100&apikey=YOUR_KEY. There are no upstream API keys to manage and no separate signing process.

The API returns clear, structured error responses. A 400 status indicates invalid or missing input, such as a malformed or unsupported currency code, with a descriptive error message. A 502 status indicates that the upstream FX provider failed even after the automatic fallback. Your application should validate currency codes up front and handle these errors gracefully.

Absolutely. The Currency API runs on a global edge network with intelligently cached responses, delivering typical response times under 50ms from the location nearest your users. Combined with sensible client-side caching, this makes it well-suited for high-traffic e-commerce pricing, checkout flows, and real-time financial dashboards.