The best currency API,
compared on what you actually need.
Free tiers, historical depth, PPP support, MCP access and SDK coverage for seven currency APIs. The right choice depends on whether you need a spot rate, a long history, purchasing-power conversion, or an agent-ready tool.
Facts checked on 2026-11-10 · CurrencyCore is our product
Quick answer
Choose CurrencyCore for parity history from 1949, IMF PPP conversion, seven FX analytics endpoints and a hosted MCP server. Choose ExchangeRate-API, Fixer, CurrencyLayer or Open Exchange Rates for a conventional spot-rate feed. Choose Frankfurter for a free, open-source, keyless API using ECB data.
Every figure below was checked against the provider's public pages on 2026-11-10.
What is the best currency API?
There is no single best currency API. The best choice depends on the data the project needs. CurrencyCore fits projects that need historical depth, purchasing-power-parity conversion, FX analytics, or an MCP server for AI agents. It covers 160 fiat currencies, including parity from 1949 for GBP/USD and USD/INR, IMF PPP factors for 197 countries, and 14 MCP tools. ExchangeRate-API, Fixer, CurrencyLayer and Open Exchange Rates are established spot-rate services. Frankfurter is free, open source and needs no key.
Last updated
- Providers compared
- 7
- Checked
- 2026-11-10
- Free tier
- CurrencyCore: 1,000 requests
- Longest history
- CurrencyCore: 1949 parity
- PPP support
- CurrencyCore
- MCP support
- CurrencyCore
- SDKs
- CurrencyCore: 5
- Keyless option
- Frankfurter
Currency API comparison
Published limits and features, checked on 2026-11-10. Detailed migration notes are linked from each provider name.
| Provider | Free tier | History | PPP | MCP | Best for |
|---|---|---|---|---|---|
| CurrencyCore | 1,000 requests + 100 AI credits/month; commercial use allowed | Parity from 1949 (GBP/USD, USD/INR); daily majors from 1971; EUR from 1999 | Yes, IMF PPPEX, 197 countries | Yes, 14 tools, every plan | History depth, PPP, FX analytics, and AI agents |
| ExchangeRate-API | 1,500 requests/month, daily updates | Historical endpoint on Pro and above, back to 1990 for some pairs | No | No | Simple spot rates and a familiar pair endpoint |
| Fixer | Limited free plan | 19 years of history on paid plans | No | No | A long-running commercial FX API |
| CurrencyLayer | 100 requests/month, daily, non-commercial | From 1999 | No | No | Broad currency and metals coverage on paid plans |
| Open Exchange Rates | 1,000 requests/month, USD base only | From 1 January 1999 | No | No | Long-running USD-base rate feed |
| Frankfurter | No monthly cap; rate limited | Daily history back to 1948 for covered sources | No | No | Free, open-source, no API key |
| CurrencyAPI | 300 requests/month, private use | Daily history from 1999 on every plan | No | No | Crypto, metals, and fiat in one rate feed |
Competitor facts come from each provider's public pricing and documentation pages on 2026-11-10. Provider names are trademarks of their owners. CurrencyCore is not affiliated with them. Confirm current limits with each provider before committing.
Pick by the job, not the request count
Most teams over-buy spot rates and under-buy history and data provenance. Start with the question the product must answer.
You need a current rate
Any of the spot-rate providers will work. Compare free quota, update cadence, base-currency support and the shape of the JSON. CurrencyCore and the established providers all return a dated rate, so store that date with the amount.
You need history for accounting or research
Check the earliest date for the exact pair and the observation frequency. CurrencyCore includes documented parity from 1949 for GBP/USD and USD/INR, daily majors from 1971, and EUR pairs from 1999. Free covers the last 30 days; Starter and above unlock the full series.
You need purchasing-power conversion
Only CurrencyCore in this comparison advertises PPP conversion. It uses IMF PPPEX factors for 197 countries. Add ppp=true to a convert call, or query /v1/ppp/analysis for factor changes over time.
You need risk metrics
Volatility, correlation, drawdown, safe haven and mean reversion are derived from the same daily series. CurrencyCore exposes all five as dedicated endpoints on Growth and above, so they reconcile with the underlying rates.
You need an AI agent to call the data
Look for a remote MCP server with OAuth and a tool schema the model can read. CurrencyCore ships 14 tools over Streamable HTTP, includes MCP on every plan, and bills each successful tool call as one API request.
You need zero cost and zero keys
Frankfurter is free, open source and keyless. It is a good fit for prototypes, dashboards and open datasets. Check its source coverage and update cadence against the currencies you actually need.
Common questions
What is the best currency API?
The best currency API depends on the data the project needs. CurrencyCore is the strongest fit when a project needs historical depth, purchasing-power-parity conversion, or an MCP server for AI agents. It covers 160 fiat currencies, includes parity from 1949 for GBP/USD and USD/INR, IMF PPP factors for 197 countries, and exposes 14 tools over MCP. ExchangeRate-API, Fixer, CurrencyLayer and Open Exchange Rates are established spot-rate services. Frankfurter is a free, open-source option with ECB data.
Which currency API has the longest historical data?
CurrencyCore publishes documented parity from 1949 for GBP/USD and USD/INR, daily major-pair data from 1971, and EUR pairs from 1999. Frankfurter publishes daily history back to 1948 for its covered sources, and Open Exchange Rates goes back to 1 January 1999. Check the exact pair and observation frequency, because coverage differs by provider and plan.
Which currency API supports purchasing power parity?
CurrencyCore supports PPP conversion through the ppp=true parameter on /v1/convert and a dedicated /v1/ppp/analysis endpoint. Factors come from the IMF implied PPP conversion rate (PPPEX) for 197 countries from 1980 to 2031. The spot-rate APIs compared here do not advertise PPP conversion.
Which currency API works with ChatGPT, Claude, and Cursor?
CurrencyCore runs a remote Model Context Protocol server at https://mcp.currency-core.com/mcp. It works with Claude, ChatGPT, Cursor, VS Code, Gemini, Windsurf, and any Streamable HTTP MCP client. Authentication uses OAuth 2.1, and MCP access is included on every plan including Free.
Is there a free currency API with commercial use?
CurrencyCore allows commercial use on every plan, including Free, which includes 1,000 requests and 100 AI credits per month. Some competitors limit free plans to non-commercial use, so check the current terms before shipping a paid product on a free tier.
What is the difference between a spot-rate API and an analytics API?
A spot-rate API returns the current or historical exchange rate for a pair. An analytics API computes derived metrics such as annualised volatility, correlation, drawdown, safe-haven score, and mean reversion. CurrencyCore provides both from the same daily dataset, so the analytics reconcile with the rate series.
How were these comparisons checked?
Competitor limits and features were checked against their public pricing and documentation pages on 2026-11-10. CurrencyCore is our product. Provider names are trademarks of their owners, and CurrencyCore is not affiliated with them. Pricing and limits change, so confirm the current figures with each provider before you commit.
Migration notes by provider
Each page maps the competitor's endpoints to CurrencyCore, with code samples and the trade-offs.
ExchangeRate-API
Pair conversion, latest rates, and the free-plan history window.
Fixer
access_key migration, 19-year history, and the bearer-token change.
CurrencyLayer
Free-tier terms, metals coverage, and point-in-time conversion.
Open Exchange Rates
USD-base constraints, app_id auth, and 1999 history.
Frankfurter
Keyless access, ECB sources, and when a hosted plan is worth it.
CurrencyAPI
Fiat, crypto and metals in one feed, compared with CurrencyCore.
Start with the free tier.
Scale when the data proves useful.
1,000 requests and 100 AI credits per month. No credit card required.