Postman is a popular tool for building, testing, and managing APIs. It provides an easy way to send requests to servers, inspect responses, and identify issues before applications go live. If you're testing geo-specific content, working behind a corporate firewall, or running Postman collections, using proxies with Postman streamlines API testing across different locations and under different network conditions.

In this tutorial, we'll demonstrate how to configure Postman proxy settings step by step, including how to troubleshoot common proxy issues.

Why Use Proxies With Postman

Postman’s built-in proxy captures HTTP/HTTPS traffic between clients and servers, which is useful for debugging API integrations and inspecting API requests. However, it doesn’t provide external proxy IPs for changing your request IP.

By routing API requests through custom proxies from reliable services like IPcook, you can send requests through high-quality IP addresses in different locations and seamlessly verify how your API behaves under different network conditions. Here are four benefits of using proxies for API development and testing:

Test APIs from multiple locations: Proxies let you send Postman requests from different countries or cities to verify location-based behavior, replicate regional errors, and check whether your API returns the correct currency, language, or localized content based on the user's location.
Verify rate limiting: Some APIs rate-limit or block connections based on IP addresses. Rotating proxies can spread API requests across different IPs, allowing you to simulate multiple users, isolate high-volume tests, and verify how your API handles traffic and rate-limiting rules.
Debug CDN latency: You can connect through an IP in a specific location to check API performance and measure the latency users may experience when connecting to CDN edge servers from different regions.
Improve privacy: Adding a proxy server creates a controlled connection between your device and the destination server. Your requests use the proxy server's connection details instead of directly exposing your original public IP address.

How to Add a Proxy in Postman

Follow these five easy steps to add and test a proxy in Postman.

Step 1. Download and Log In to Postman

To begin, download the latest Postman version if you do not have it on your computer. After installation, launch the application and log in or register an account. Then you're ready to set up your proxy.

Step 2. Open Postman Proxy Settings

On the menu, click the gear icon in the top-right corner and select App settings.

In the Settings window, select Proxy from the left sidebar and go to the Proxy configurations for sending requests section.

Step 3. Enable a Custom Proxy Configuration

If you are using proxies from a third-party service like IPcook, enable Use custom proxy configuration. Under Use proxy for, keep HTTP and HTTPS selected if you want both request types to use the proxy.

Enable Custom Proxy Configuration in Postman

Step 4. Add Your Proxy Details

Scroll down to the Proxy server section. Choose the proxy protocol from the dropdown to match the proxy you're using.

If you don't have a proxy yet, IPcook now offers 100MB of free residential proxy traffic. Don't miss out!

Get your IPcook proxy in just a few clicks. Sign up on the IPcook dashboard, navigate to Residential, and head to Proxy Generator. Choose your target country or city, select HTTP or SOCKS5, and choose the rotation mode that fits your task. Next, select your sub-account and configure the remaining proxy settings. You can then get your proxy host and port, plus your username and password.

The general process is almost the same for IPcook ISP proxies, IPcook Datacenter Proxies, and other proxy types. Visit our quick start guide for more details.

Back in Postman, enter the proxy host and port. Then toggle Proxy auth and enter the proxy username and password.

In some cases, you may want specific URLs or IP addresses to avoid using the proxy server. You can add them to the Proxy bypass field.

After everything is entered, close the Settings window. Your custom proxy is now ready to use in Postman.

Step 5. Test the Proxy Connection

Once you have entered the details, test the proxy to make sure that it is functional.

Click the + icon to open a new request tab. Select GET, enter https://api.ipify.org?format=json, and click Send.

Check the IP address returned in the response. If it shows the IP provided by your proxy service, the proxy connection works correctly.

Troubleshooting Common Postman Proxy Issues

If your proxy doesn't work as expected in Postman, check the proxy configuration, authentication details, and network settings. Here are some common issues and ways to fix them.

1. 407 Proxy Authentication Required

When you send a request, you may see a 407 Proxy Authentication Required status in the response area. This usually means that the proxy requires authentication or the authentication details are incorrect.

Make sure Proxy auth is enabled and check that the correct username and password are entered in the custom proxy settings.

407 Proxy Authentication Required in Postman

2. Connection Timeout or Connection Failed

If Postman can't send a request through the proxy, the request may time out, or you may see an error message in the response area instead of a normal API response. You can also open the Console from the Postman footer to view more details about the failed connection.

First, check the proxy address and port to make sure Postman can connect to the proxy server. You can also try sending the same request without the proxy. If the request works without the proxy, the problem is more likely related to the proxy connection or configuration. Firewalls or other security measures may also be filtering the traffic.

3. Proxy IP Does Not Change

If an IP-checking request still returns your original public IP address, make sure Use custom proxy configuration is enabled and review the proxy details you entered. Then send the request again.

4. System Proxy or Environment Variables Affect the Connection

Postman can also use proxy settings from your operating system. If your request isn't using the custom proxy you expect, system proxy settings or proxy environment variables may be affecting the connection.

Check whether your system has proxy variables like http_proxy, https_proxy, HTTP_PROXY, or HTTPS_PROXY. If you don't need them, remove or disable them and try the request again.

5. SSL or Certificate Errors

If an HTTPS request fails with an SSL or certificate error, Postman may be unable to verify the certificate used for the connection. This can happen because of certificate issues that prevent a secure connection from being established. Check the SSL and certificate settings in App settings, and use the Postman Console to view more details about the connection.

Final Word

That wraps up our guide on configuring proxies in Postman. With IPcook, you can route Postman API requests through global IPs to test location-based APIs, replicate IP- or location-specific issues, avoid blocks, and debug with precision while keeping your online activities private.

Start Secure API Testing with High-Quality IPs Now!

How to Configure Postman Proxy Settings