How to Send Form Data in Postman: Step-by-Step Guide

To send form data in Postman, select the Body tab, then choose either x-www-form-urlencoded or form-data as the data type. Enter your key-value pairs for the form fields, then send the request to submit the form data.

Syntax

In Postman, form data is sent in the Body section of the request. You can choose between two main types:

• x-www-form-urlencoded: Encodes form fields as URL-encoded key-value pairs.
• form-data: Sends data as multipart/form-data, useful for files and text fields.

Each key represents a form field name, and the value is the field content.

http

POST /your-api-endpoint HTTP/1.1
Host: example.com
Content-Type: application/x-www-form-urlencoded

key1=value1&key2=value2

Example

This example shows how to send form data using x-www-form-urlencoded in Postman to submit a login form with username and password.

http

POST https://example.com/api/login

Body tab:
- Select <code>x-www-form-urlencoded</code>
- Add key: <code>username</code>, value: <code>user123</code>
- Add key: <code>password</code>, value: <code>pass123</code>

Output

HTTP/1.1 200 OK
{
  "message": "Login successful",
  "token": "abc123xyz"
}

Common Pitfalls

• Not selecting the Body tab or wrong data type causes the server to not receive form data.
• Using raw body type instead of x-www-form-urlencoded or form-data for form submissions.
• For file uploads, forgetting to use form-data and the file input type.

http

Wrong way:
POST https://example.com/api/login

Body tab:
- Select <code>raw</code>
- Enter JSON: {"username":"user123","password":"pass123"}

Right way:
POST https://example.com/api/login

Body tab:
- Select <code>x-www-form-urlencoded</code>
- Add key: <code>username</code>, value: <code>user123</code>
- Add key: <code>password</code>, value: <code>pass123</code>

Quick Reference

• Body tab: Choose x-www-form-urlencoded for simple form fields.
• Body tab: Choose form-data for files or mixed data.
• Key-value pairs: Enter form field names and values.
• Headers: Postman sets Content-Type automatically based on body type.

Key Takeaways

Always select the Body tab and choose the correct form data type before sending.

Use x-www-form-urlencoded for simple key-value pairs and form-data for file uploads.

Enter form fields as key-value pairs to simulate form submission accurately.

Avoid using raw JSON when the API expects form data format.

Postman automatically sets the Content-Type header based on your body selection.