For programmatic, intraday-fresh FX rates with per-value provenance and MCP-native access, exchangerate.dev is the stronger default. Keep AllRatesToday if its ready-made SDK for your exact language already fits your stack.
If your rates flow into code — payments, dashboards, backtests — exchangerate.dev fits how you already work. Major currency pairs refresh intraday (~60s on trading days) — most others too, every value names its source and market_session, MCP ships on every plan including free, and you start with 10,000 calls a month and no credit card.
AllRatesToday matches ~60-second freshness, ships an MCP server, and offers official SDKs across more languages than most FX APIs, including a ready-made React component. If a drop-in SDK for your exact stack is what you need, that breadth is real. exchangerate.dev differentiates on per-value source + market_session labelling.
Choose exchangerate.dev when intraday freshness, per-value provenance, MCP-native access, and free-tier headroom matter. Keep AllRatesToday if its ready-made SDK for your exact language already fits your stack. Both speak REST JSON over HTTPS, and exchangerate.dev accepts Frankfurter-compatible parameters — so trying it is low-risk.
Rates are from the free tier, updated intraday on trading days. Indicative only, not for settlement or regulated trading.