CurrencyFreaks vs National Bank of Poland

CurrencyFreaks delivers minute-level exchange rates for a notably broad basket — 166 fiat currencies plus metals and roughly 850+ cryptocurrencies, over 1,000 instruments in total — with both JSON and XML output and historical data reaching back to 1984. Its paid tiers unlock faster refresh intervals, a time-series endpoint, a fluctuation endpoint, and even an IP-to-currency lookup, positioning it as a more data-dense alternative to typical fiat-only rate APIs.

The National Bank of Poland's Web API exposes the official mid-market currency reference rates it publishes daily across three rate tables, plus historical gold-price fixings dating back to January 2013 — all queryable by date, currency code, or table series via plain HTTP GET. Responses come back in JSON or XML depending on a format parameter, though historical range queries are capped at 93 days per request. The bank retired plain HTTP in August 2025 in favor of HTTPS-only access.