Download and Install Postman and Fiddler

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Download and Install Postman and Fiddler

When working with APIs and web applications, developers often need specialized tools to test, debug, and monitor HTTP requests and responses. Two commonly used tools are Postman (for API testing and development) and Fiddler (for capturing and analyzing network traffic). In this course, we will use both of these tools.

What is Postman?

Postman is a powerful collaboration platform for API development. It provides a user-friendly interface for sending HTTP requests, testing APIs, and automating workflows. Developers and testers widely use Postman to work with REST, SOAP, and GraphQL APIs.

• API Testing: Create and send GET, POST, PUT, DELETE, and PATCH requests easily.
• Automation: Build collections and scripts to automate testing workflows.
• Collaboration: Share collections with teams and maintain version control.
• Cross-Platform: Available for Windows, macOS, and Linux.

Postman is the go-to tool for working with APIs in development and testing.

How to Download and Install Postman

1. Visit the Official Website
   • Go to: https://www.postman.com/downloads/
2. Choose Your Operating System
   • Options include Windows (64-bit), macOS, and Linux.
   • For Windows, you can choose the standard installer (.exe) or the Windows 64-bit ZIP archive.
3. Download the Installer
   • Click Download for your OS.
   • The file size is usually around 100–150 MB.
4. Run the Installer
   • Double-click the downloaded file (Postman-win64-x.x.x-Setup.exe).
   • Follow on-screen instructions. No complex setup is needed.
5. First Launch
   • Once installed, launch Postman from the Start Menu or desktop.
   • You can sign in with a Postman account to sync collections, or continue without signing in.

At this point, Postman is ready, and you can start testing APIs.

What is Fiddler?

Fiddler is a web debugging proxy tool developed by Telerik (now part of Progress). It allows you to capture, inspect, and analyze HTTP and HTTPS traffic between your computer and the internet. Fiddler is especially useful for troubleshooting API calls, debugging web applications, and monitoring performance.

• Traffic Capture: Logs all HTTP/HTTPS requests and responses.
• Debugging: Inspect headers, cookies, query strings, and payloads.
• Performance Testing: Monitor response times and identify bottlenecks.
• API Testing: Modify requests and responses to simulate scenarios.
• Security Testing: Analyze HTTPS traffic by installing a root certificate.
• Extensible: Plugins and scripting support for advanced usage.

Fiddler acts as a middleman between your application and the internet, giving you visibility into every request and response.

How to Download and Install Fiddler

1. Visit the Official Website
   • Go to: https://www.telerik.com/fiddler
2. Choose the Right Version
   • Fiddler Classic: The original version, stable and widely used for Windows.
   • Fiddler Everywhere: A newer, cross-platform version available for Windows, macOS, and Linux.
3. Download the Installer
   • Click Download under your preferred version.
   • For Windows, the .exe file is typically around 50 MB.
4. Run the Installer
   • Double-click the downloaded installer.
   • Accept the license agreement.
   • Follow the wizard to complete the installation.
5. First Launch
   • Open Fiddler from the Start Menu or desktop shortcut.
   • By default, it starts capturing HTTP/HTTPS traffic.
   • If you are working with HTTPS, you may need to enable SSL decryption (Fiddler will guide you through the process of installing its root certificate).

Now you can monitor and debug traffic between your computer and servers.

Postman vs. Fiddler: When to Use Each

• Postman
  1. Best for API development and testing.
  2. Used when you need to create and send API requests.
  3. Suitable for automating API test cases and workflows.
• Fiddler
  1. Best for debugging and monitoring traffic.
  2. Used when you need to see what’s happening behind the scenes between client and server.
  3. Suitable for troubleshooting errors, performance issues, and security analysis.

In the industry, many developers use both tools together: Postman for sending requests and Fiddler for analyzing the network traffic.