Currencylayer and ExchangeRate-API are both REST FX rate APIs. The real differences are free-tier size, update frequency, and where each one starts charging — the table below has the specifics.
Currencylayer's free tier: 100 API calls/month, daily updates. ExchangeRate-API's free tier: 1,500 requests/month, updates once per day. Check both against your expected monthly call volume before committing — a restricted base currency or a low monthly cap can force an upgrade sooner than the sticker price suggests.
Currencylayer updates daily on Free; hourly on Basic; every 10 minutes on Enterprise ($59.99/mo); every 60 seconds on Enterprise+ ($99.99/mo). ExchangeRate-API updates once daily on Free; every 60 minutes on Pro ($10/mo); every 5 minutes on Business ($30/mo). Currencylayer sources data from financial data partners and central bank reference rates, per currencylayer's own documentation. ExchangeRate-API sources data from aggregated published sources, per ExchangeRate-API's own documentation.
Once the free tier runs out, Currencylayer's cheapest paid plan is basic plan, $14.99/month, for 10,000 calls/month with hourly updates. ExchangeRate-API's cheapest paid plan is pro plan, $10/month ($100/year with the annual discount), for 30,000 requests/month with updates every 60 minutes.
Currencylayer: 100 API calls/month, daily updates. ExchangeRate-API: 1,500 requests/month, updates once per day.
Currencylayer updates daily on Free; hourly on Basic; every 10 minutes on Enterprise ($59.99/mo); every 60 seconds on Enterprise+ ($99.99/mo). ExchangeRate-API updates once daily on Free; every 60 minutes on Pro ($10/mo); every 5 minutes on Business ($30/mo). Compare the specific plan you'd actually pay for, not just the headline tier — both vendors gate faster updates behind higher plans.
Neither currently does. No MCP (Model Context Protocol) integration is listed on currencylayer's product pages. No MCP integration is listed on ExchangeRate-API's site.
Currencylayer's cheapest paid plan is basic plan, $14.99/month, for 10,000 calls/month with hourly updates. ExchangeRate-API's cheapest paid plan is pro plan, $10/month ($100/year with the annual discount), for 30,000 requests/month with updates every 60 minutes. Compare against your actual monthly call volume, not just the sticker price — overage and rate-limit behavior varies by plan.
If you're choosing between Currencylayer and ExchangeRate-API mainly on free-tier size or update frequency, exchangerate.dev is worth a look too: a free tier of 10,000 calls/month across 465 pairs, no credit card required, major pairs updating roughly every 60 seconds on trading days, a source and market_session field on every response, and an MCP stdio bridge on every plan including free — a capability neither Currencylayer nor ExchangeRate-API currently lists.
Rates are from the free tier, updated intraday on trading days. Indicative only, not for settlement or regulated trading.