The Best Exchange Rate APIs in 2026: A Developer's Comparison

Picking an exchange rate API looks simple until you read the plan tables: one free plan allows 100 requests a month, another 1,500; one quotes against any base currency, another only against the US dollar; one updates hourly for free, another daily. This comparison puts five popular APIs side by side on the questions developers actually ask, using only facts stated on each provider's own pricing and documentation pages.

We make one of them, FxFeed, so read this with that in mind. We have tried to be fair: every competitor fact below links to where it came from, and the "choose it if" notes include the cases where another API is the better fit.

Information checked September 2026. Plans and prices change; follow the links to each provider's pricing page for current details.

The short version

	FxFeed	Open Exchange Rates	Fixer	ExchangeRate-API	currencyapi
Free requests / month	1,000	1,000	100	1,500	300
Free plan updates	Daily	Hourly	Hourly	Daily	Daily
Free plan base currency	Any	USD only	Paid plans list "All Base Currencies"	Any	Not stated
Historical rates on free plan	Yes	Yes	Yes	No (Pro and up)	Yes
Cheapest paid plan	$9/month	$12/month	$14.99/month	$10/month	$9.99/month
Its requests / month	20,000	10,000	10,000	30,000	15,000
Its updates	Hourly	Hourly	Hourly	Every 60 minutes	Hourly
Currencies	160+	200+	170	165	Not stated on pricing page

The rest of this article explains what those rows mean in practice and where each API stands out.

What to compare

Free plan size. A free plan is how you evaluate an API, and for side projects it is often all you need. Count what you will really use: one request per page view adds up quickly, while a cached integration might need a few hundred requests a month.

Base currency. If your app prices in euros, you want rates against EUR. An API that only quotes against USD can still work, since you can divide two USD rates to get a cross rate, but it is extra code, and it is where subtle rounding bugs live.

Update frequency. Daily rates are fine for invoicing, accounting, reporting and most e-commerce. Hourly or faster matters for dashboards and anything that shows a "live" rate. Trading needs streaming market data, which none of these APIs is designed for.

Historical data. Anything that values a transaction at the rate of its date needs history: invoices, expense reports, tax records, backtests.

Price per request at your scale. Compare the plan you would actually need in a year, not the cheapest one.

FxFeed

FxFeed is a JSON API over HTTPS with four endpoints, /latest, /historical, /convert and /timeseries, at https://api.fxfeed.io/v2. The free plan includes 1,000 requests a month with daily data, any base currency and historical rates, with no credit card. Paid plans add hourly data and start with Starter at $9 a month for 20,000 requests; larger plans are on the pricing page. It covers 160+ currencies with history back to 1999, and is made and hosted in Europe.

Where it stands out:

• Any base currency and historical rates on every plan, including the free one.
• A low entry price for hourly data.
• Integrations beyond code: custom functions for Google Sheets and a remote MCP server for AI assistants, both described in the docs.

Choose it if you want any base currency and historical rates on a free or inexpensive plan, or you are building in Europe. Look elsewhere if you need updates more often than hourly, or the longest currency list.

Where the rates come from and how often they refresh is documented on the methodology page.

Open Exchange Rates

According to Open Exchange Rates' signup and pricing page, the free plan allows up to 1,000 requests a month with hourly updates, with USD as the only base currency. The Developer plan costs $12 a month for 10,000 requests with hourly updates and all base currencies; higher plans update every 30 minutes (Enterprise, $47 a month) or every 5 minutes (Unlimited, $97 a month), and annual billing includes two months free. It covers 200+ currencies, with history back to 1999.

Choose it if you want hourly updates on a free plan, need the widest currency list here, or need updates every few minutes and can pay for them. The free plan's USD-only base means converting between two other currencies needs a cross-rate calculation.

Side by side: FxFeed vs Open Exchange Rates.

Fixer

Fixer's pricing page lists a free plan of 100 API calls a month with hourly updates, SSL encryption and historical data. "All Base Currencies" is listed from the paid Basic plan up. Basic costs $14.99 a month ($13.99 a month billed yearly) for 10,000 calls with hourly updates; Professional ($59.99 a month) updates every 10 minutes and Professional Plus ($99.99 a month) every 60 seconds. It covers 170 currencies with history back to 1999.

Choose it if you need updates every 10 minutes or every minute and are comfortable at its price points. The 100-call free plan is enough to evaluate the API, but little more.

Side by side: FxFeed vs Fixer.

ExchangeRate-API

ExchangeRate-API's home page pricing lists a free plan of 1,500 requests a month with daily updates, and any base currency. Its Pro plan costs $10 a month or $100 a year for 30,000 requests with updates every 60 minutes, and Business costs $30 a month for 125,000 requests with updates every 5 minutes. It supports 165 currencies.

Historical data is the main difference: its historical data documentation says it is "only available to users on our Pro, Business or Volume plans", covering all supported currencies from 1 January 2021 and a set of 35 currencies from 1990 to 2020.

Choose it if you need the largest free request allowance in this list and only need current rates, or want a generous paid tier with frequent updates. If you need historical rates for free, or history for many currencies before 2021, look elsewhere.

Side by side: FxFeed vs ExchangeRate-API.

currencyapi

currencyapi's pricing page lists a free plan of 300 requests a month with daily updates and historical rates. The Small plan costs $9.99 a month for 15,000 requests with hourly updates; Medium ($39.99 a month, 600,000 requests) and Large ($79.99 a month, 1,700,000 requests) update every 60 seconds, and yearly billing is discounted.

Choose it if you need a very large number of requests with minute-level updates at a mid-range price. Its free plan is the second smallest here, so budget for caching during evaluation.

So which one?

There is no single best API, only a best fit for what you are building:

• A side project, prototype or internal tool: a free plan with any base currency and history covers most needs. FxFeed and ExchangeRate-API have the largest free allowances; FxFeed's includes historical rates.
• E-commerce prices, invoicing and accounting: daily or hourly rates plus history on the date of each transaction. Compare FxFeed, Open Exchange Rates and ExchangeRate-API's Pro plan at your expected volume.
• Dashboards that should look live: hourly is usually enough; minute-level updates are available from Fixer, currencyapi, Open Exchange Rates and ExchangeRate-API on their higher plans.
• The widest currency coverage: Open Exchange Rates lists 200+.

Whatever you choose, two habits keep costs down on any of them: cache rates rather than requesting them per page view, and fetch every currency for a base in one request instead of one pair at a time. Our guides for Python, JavaScript and Node.js and Google Sheets show both.

Try FxFeed

The quickest way to judge an API is to call it. Get a free API key, no credit card required, and make your first request from the documentation, or browse the supported currencies first. For the full comparison tables, see Compare FX rate APIs.