Postman is the most popular API testing tool for developers. It simplifies API development with an intuitive interface, powerful collections, and automated testing. Whether you're building REST, GraphQL, or gRPC APIs, Postman has you covered.

This tutorial covers everything from basics to advanced features in Postman 2026.

Getting Started with Postman

Installation

Creating an Account

First API Request

Creating a Request

  1. Open Postman and click "New Request"
  2. Enter the API URL: https://api.example.com/users
  3. Select HTTP method: GET, POST, PUT, DELETE, etc.
  4. Click "Send"
  5. View response in the bottom panel

Common HTTP Methods

Method Description Example
GET Retrieve data GET /users
POST Create data POST /users
PUT Update data PUT /users/123
PATCH Partial update PATCH /users/123
DELETE Remove data DELETE /users/123

Postman Collections

What are Collections?

Collections organize API requests into logical groups. Perfect for APIs with many endpoints.

Creating a Collection

  1. Create a few related requests
  2. Select the requests (Cmd/Ctrl + click)
  3. Click "Save to Collection"
  4. Create a new collection or add to existing
  5. Organize with folders inside collections

Collection Structure Example

My API Collection
├── Authentication
│   ├── Login
│   ├── Register
│   └── Refresh Token
├── Users
│   ├── Get All Users
│   ├── Get User by ID
│   ├── Create User
│   ├── Update User
│   └── Delete User
└── Posts
    ├── Get Posts
    ├── Create Post
    ├── Update Post
    └── Delete Post

Environments

Managing Multiple Environments

Environments let you manage variables for different stages (dev, staging, production).

Creating Environments

  1. Click the environment selector (top right)
  2. Click "Add"
  3. Name it: "Development"
  4. Add variables:
    • base_url: https://dev-api.example.com
    • api_key: dev-key-123
  5. Create "Staging" and "Production" environments similarly

Using Environment Variables

In your requests, reference variables with {{variable_name}} syntax:

URL: {{base_url}}/users
Headers:
  Authorization: Bearer {{api_key}}

Authentication

Bearer Token (JWT)

  1. Go to Headers tab in your request
  2. Add header:
    • Key: Authorization
    • Value: Bearer {{jwt_token}}

API Key

  1. Add header:
    • Key: X-API-Key
    • Value: {{api_key}}

OAuth 2.0

Postman supports OAuth 2.0 flows:

  1. Click "Authorization" tab
  2. Select "OAuth 2.0" from Type dropdown
  3. Configure callback URL, auth URL, token URL
  4. Click "Get New Access Token"
  5. Use token automatically in requests

Automated Testing

Writing Tests

Add tests to requests using the "Tests" tab. Postman evaluates tests after receiving the response.

Example Tests

// Test status code
pm.test("Status code is 200", function () {
    pm.response.to.have.status(200);
});

// Test response time
pm.test("Response time is less than 200ms", function () {
    pm.expect(pm.response.responseTime).to.be.below(200);
});

// Test response body has specific field
pm.test("Response has user ID", function () {
    const jsonData = pm.response.json();
    pm.expect(jsonData.id).to.exist;
});

// Save value from response for next request
const jsonData = pm.response.json();
pm.environment.set("user_id", jsonData.id);

Running Tests

Pre-Request Scripts

Run JavaScript before requests for dynamic data, timestamps, or authentication.

Examples

// Generate timestamp
const timestamp = Date.now();
pm.environment.set("timestamp", timestamp);

// Generate random data
const userId = Math.floor(Math.random() * 1000);
pm.environment.set("random_user_id", userId);

// Hash data for authentication
const crypto = require('crypto-js');
const hashedPassword = crypto.SHA256(pm.environment.get("password")).toString();
pm.environment.set("hashed_password", hashedPassword);

Mock Servers

Postman lets you create mock servers that simulate API responses. Perfect for frontend development when the backend isn't ready.

Setting Up a Mock Server

  1. Open a collection
  2. Click "..." menu → "Mock collection"
  3. Postman generates a mock URL: https://mockserver-id.mock.pstmn.io
  4. Add examples to each request with different responses

Adding Examples

GraphQL Support

Creating GraphQL Requests

  1. Create new request
  2. Change type from "GET" to "GraphQL"
  3. Enter query or mutation
  4. Click "Send"

Example GraphQL Request

query GetUser($id: ID!) {
  user(id: $id) {
    id
    name
    email
  }
}

Variables:
{
  "id": 123
}

Monitors (Paid Plans)

Monitors run your API requests on a schedule and alert you if they fail. Essential for production monitoring.

Setting Up a Monitor

  1. Open collection → "Monitors" tab
  2. Click "Create Monitor"
  3. Configure:
    • Name: "User API Health Check"
    • Request: Select from collection
    • Frequency: Every 5 minutes
    • Region: US-East
    • Alerts: Email, Slack, PagerDuty

Team Collaboration

Sharing Collections

  1. Open collection → "Share"
  2. Generate share link (for anyone)
  3. Or invite team members (for private access)
  4. Team can fork collections and make changes

Workspaces

Workspaces let teams collaborate in real-time:

Advanced Features

API Documentation

Generate API documentation from collections:

  1. Open collection → "..." menu
  2. Select "View in web"
  3. Postman generates documentation automatically
  4. Share documentation link

API Design

Design APIs before implementing:

  1. Create "New API Definition"
  2. Design endpoints with OpenAPI/Swagger spec
  3. Generate mock servers automatically
  4. Generate code stubs

Import/Export

2026 Updates

Postman 11.0

Best Practices

1. Organize Collections

2. Use Environment Variables

3. Write Tests

4. Use Pre-Request Scripts

Getting Started Checklist

Day 1

Week 1

Week 2+

Conclusion

Postman is an essential tool for API development. Start with basic requests and collections, then explore environments, tests, and mock servers as your needs grow.

For individuals, the free account is sufficient. For teams, consider the Basic or Professional plans for better collaboration and monitoring features.

Affiliate Disclosure

This article contains affiliate links to Postman. If you click through and sign up for a paid plan, I may earn a commission at no additional cost to you. I use Postman daily for API testing and recommend it to all API developers.