As simple as one, two, three!


Register as a developer

First of all you need to register as a developer. This is so that we know who you are and how to get in touch with you.

To register you just need to fill out this form.

Our integration support will come back to you with a sandbox account and the authorization information for your application.


Authorize your application

You’ve got your Authorization-Code and your Client-Secret, these will be the keys to get the final Access-Token. The Access-Token combined with the Client-Secret is used to authorize against the API.

Your client information is unique for your application. Combined with the Access-Token it connects to a specific Fortnox account.

To retrieve your Access-Token you simply send a request to our API using the headers “Authorization-Code” and “Client-Secret”.

Here’s an example using cURL

curl -X "GET" "" \
     -H "Authorization-Code: 03b8d2b5-cade-c544-7a59-5a1ac8665856" \
     -H "Client-Secret: BFr3jKKZ1J" \
     -H "Content-Type: application/json" \
     -H "Accept: application/json"

Making your request

With the Access-Token you just received you can start making requests and develop against our API.

Start by going through our documentation to see which data is available and how to use it. If there are any questions, please don’t hesitate to contact us!