Finance

Financial APIs.

Coin Boss API

Coin Boss is a free public REST API for real-time crypto derivatives market data. Developers call the documented endpoints (anonymous use needs no key) and get JSON for liquidations, open interest, funding rates, long/short ...

API, JSON, REST

Questions

Which free finance APIs work without an API key?

Coin Boss API works without a key, according to its documentation. Most keyless services ask you to keep the number of requests reasonable, and some ask for a User-Agent that names your app.

Are these finance APIs really free?

The services here can be used without paying, at least on a free plan or free tier, often with limits such as a number of requests per day or non-commercial use only. The table above quotes what each service says about its free use; check the provider's own terms before you rely on it.

How up to date is this list?

The address of every service is checked about once a week, and services that stop working or stop being free are removed. This list last changed on November 1st, 2026.