How to create API requests?

How to create API requests to SendFox: get an access token, authorize in Postman, and build a POST request that adds a contact to a list—step by step.

Before you start

The SendFox API is included with paid plans. On the Free plan every request returns HTTP 402 with "API access requires a paid plan."
All endpoints build from https://api.sendfox.com—see the endpoints reference.
This walkthrough uses the Postman app, but the same steps work in any HTTP client.

Step 1: Create the request in Postman

Click New, add the request name and collection, and click Save.

Postman new request dialog with a request name and collection selected

Step 2: Get your SendFox access token

In SendFox, go to Settings → Connections → API tokens.
Click Create New Token, name it, and click Create.
Copy the personal access token immediately—it's only shown once. (Full details: how to get access tokens.)

SendFox API tokens settings page with the Create New Token link

Step 3: Authorize the request

Back in Postman, open the Authorization tab.
Choose Bearer Token (or OAuth 2.0) as the type and paste the access token you generated in SendFox.

Postman Authorization tab with the SendFox access token pasted

Step 4: Write the request

Here's an example POST request that adds an email address and first name to a specific SendFox list.

Select POST from the dropdown menu and use this URL: https://api.sendfox.com/contacts

Postman request with POST selected and the SendFox contacts URL

Add email as a Key and the email address as its Value.

Postman parameters with the email key and address value

Do the same for first_name.

Postman parameters with the first_name key added

To target a list, get its ID: in SendFox go to Audience → Lists, open the list, and copy the number from the page URL.

SendFox list page URL showing where to copy the list ID

Add the list as a lists[] parameter with your list's ID as the value (your ID will differ from the example).

Postman parameters with the lists array key and a list ID value

Lastly, add an Accept: application/json header on the Headers tab so error responses come back as readable JSON.

Postman Headers tab with the Accept application/json header

Step 5: Test the request

Click Send. A successful request returns the new contact as JSON:

Postman response showing the created contact JSON

And the contact appears on your SendFox list:

SendFox list showing the contact added through the API

Troubleshooting

HTTP 402: "API access requires a paid plan."

The API is locked on the Free plan—upgrade to use it.

HTTP 401 Unauthorized

The token is missing, mistyped, or revoked. Re-check the Authorization tab and create a fresh token if needed.

HTTP 4xx validation errors

Check the JSON response message—usually a missing required parameter (for example, email on POST /contacts). The Accept: application/json header makes these messages readable.
Still stuck? Visit the SendFox Help Center at help.sendfox.com.

Frequently Asked Questions

What other endpoints can I call?

See the endpoints reference and the complete documentation at sendfox.com/developer/docs.

Do I have to use Postman?

No—any HTTP client works (curl, your own code, no-code tools). The pattern is the same: Bearer token in the Authorization header, JSON responses.

Is there a no-code option?

Yes—Zapier covers most automation needs without writing requests by hand.