Make your first API call in a minute, no sign-up

Your product needs UK company data. Integration shouldn't take a sprint.

How fast can you get a real answer from the CompanyStack API? Here's your first call, from the browser.

The API page has a live console. Pick an endpoint, here the company profile, type a company number and send the request. You don't need to sign up: it uses the website's shared demo key.

The answer comes straight from the production API: the status code, the round trip, and how much of the allowance is left this minute and today, then the JSON itself, with the register details, filing deadlines and charges.

Below it, the same request is written out in cURL, JavaScript and Python, ready to paste into your code with your own key.

The documentation publishes the plans and their limits: on the free plan, 30 requests a minute and 1,000 a day, shared by all your keys, with a 429 and a Retry-After header when you reach them.

And the whole API is described in an OpenAPI 3.1 specification, so you can generate a client in your own language.

1,000 requests a day free, and 10,000 on Starter.

Try the API before you write a line of code. companystack.co.uk.