Postman

Postman is the world's most widely used tool for working with APIs. It's built by the company of the same name and used by development teams from small startups to giants like Microsoft, Meta, Stripe, and PayPal. It's for anyone who wants to connect to a service via an API – whether you're building one or just testing someone else's.

It works simply: you set the address (URL) and request type, add any parameters or credentials, hit Send, and instantly see the server's response – the data, the status code, and how long it took to arrive. Instead of tedious debugging in code, you immediately verify whether the API returns what it should.