How to Send Headers in Postman: Step-by-Step Guide

To send headers in Postman, open your request, go to the Headers tab, and add key-value pairs for each header you want to send. Postman includes these headers automatically when you send the request.

Syntax

In Postman, headers are sent as key-value pairs under the Headers tab of your request. Each header has a Key (header name) and a Value (header content).

Example headers include Content-Type, Authorization, and Accept.

text

Key: Content-Type
Value: application/json

Key: Authorization
Value: Bearer your_token_here

Example

This example shows how to send a JSON POST request with an Authorization header and Content-Type header in Postman.

http

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

Headers:
Content-Type: application/json
Authorization: Bearer abc123token

Body (raw JSON):
{
  "name": "John",
  "age": 30
}

Output

Status: 200 OK
Response Body:
{
  "success": true,
  "message": "Data received"
}

Common Pitfalls

• Forgetting to add the Content-Type header when sending JSON causes the server to misinterpret the data.
• Using incorrect header names or typos prevents the server from recognizing your headers.
• Not including authorization headers when required leads to authentication errors.
• Headers set in the Headers tab override any automatic headers Postman adds.

text

Wrong way:
Key: content-type
Value: application/json

Right way:
Key: Content-Type
Value: application/json

Quick Reference

Header Name	Purpose	Example Value
Content-Type	Tells server the data format	application/json
Authorization	Sends credentials or tokens	Bearer abc123token
Accept	Tells server what response formats are accepted	application/json
User-Agent	Identifies the client software	PostmanRuntime/7.29.0

Key Takeaways

Add headers as key-value pairs in the Headers tab before sending your request.

Always use correct header names with proper capitalization.

Include Content-Type header when sending JSON or other data formats.

Authorization headers are required for protected APIs.

Headers in Postman override automatic headers if set manually.