Postman Proxy: Configure Settings & Fix Common Errors
Tutorials
Milena Popova
Key Takeaways
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Postman allows you to easily create, manage, and test APIs without complicating the technical side of development too much.
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Using proxy servers with Postman increases the control of the traffic you send through your API, which helps improve security, performance, and testing capabilities.
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You can configure a proxy in Postman or set global proxies in your operating system's settings.
More than half of all internet traffic is created by APIs (Application Programming Interfaces), according to Cloudflare . That’s how much we rely on different systems communicating with one another for the internet to function. Platforms like Postman that help build, test, and monitor APIs are equally important.
In many cases, Postman use can be improved or even enabled by using a proxy server sitting between Postman and the API. Configuring Postman to use proxies isn’t that difficult, as there are direct implementation settings you just need to fill in.
Postman Proxy vs System Proxy
System proxies force Postman to act like any other app on your computer by following the operating system’s global proxy settings. It’s most useful in business settings when connecting or working with corporate servers or databases.
A custom proxy for Postman is a specific intermediary server that lets you route only Postman’s requests without affecting the rest of your system. It’s often used to bypass limits, stress test APIs developed on Postman, or simply add more utility to Postman.
| System Proxy | Custom Proxy in Postman | |
|---|---|---|
| Definition | Postman uses the proxy settings defined in your OS or environment variables. | Postman uses a manual proxy configuration defined inside its settings. |
| Scope | Affects Postman and all other apps on your device. | Affects only requests sent from Postman. |
| Primary Use Case | Corporate compliance, remote access, firewall requirements. | Testing different geo-locations, debugging specific API behavior, bypassing local network restrictions, or IP masking. |
| Flexibility | Low. All changes affect the whole device. | High. Can be toggled on/off instantly for specific tests. |
| Precedence | Lower priority. Overridden by custom proxy in Postman. | Higher priority. Works on top of the system Proxy settings. |
Benefits of IPRoyal Proxies for Postman
Using reliable residential proxies helps your API calls appear genuine and avoid being blocked for sending too many requests during testing. Other proxy types, such as datacenter proxies, can work as well, but they are easier to detect and lack certain key features.
Reliable IP Rotation for API Testing
Postman doesn’t have native settings for proxy server rotation, which is crucial when you need a more stable access and success rates. Premium rotating proxy networks have flexible IP rotation to change the exit IP per request, session, or defined timeframe. As such, your API calls are spread across many IPs without complicating the setup.
Testing APIs From Multiple Locations
A quality residential proxy service will ensure large and diverse pools of IPs from all around the world. You can test how Postman requests will play out from many different locations with a couple of clicks. This lets you verify location-based behavior, replicate errors, and perform other tasks without setting up infrastructure in each region yourself.
Avoiding IP Bans and Rate Limits
Some APIs or related services rate-limit or even block connections based on IP addresses. Residential proxies ensure you’ll appear as a genuine user with each request, reducing the chances of aggressive throttling during heavy tests. Low-quality or other types of proxies are more likely to be blacklisted or detected.
IPRoyal’s residential proxies can ensure all of these benefits and more for an affordable price. Ensure IP rotation, choose from over 195 proxy server locations, and avoid limitations with genuine residential IPs. No limits for concurrent sessions and no complicated long-term contract, simply subscribe and use our proxies with Postman.
Global Pool, Precise Targeting, Zero Contracts
Premium Residential Proxies
How to Configure a Postman Proxy?
Up to this point, you should be able to judge whether using a proxy for Postman is worth it in your use case. There are two options for configuring a proxy server that will reroute your Postman API requests. You can use your system’s proxy settings or a custom proxy configuration in the Postman app.
Use System Proxy Settings
When you enable system proxy settings in Postman, the software will use your device’s proxy configuration to send API requests. Here’s how to do it:
Step 1: Open Postman
Launch the Postman app on your computer.
Step 2: Go to Settings
Click the gear icon (1) and select ‘Settings’ (2) from the menu.
Step 3: Open the Proxy Tab
Click on ‘Proxy’ (3) in the sidebar menu.
Step 4: Enable System Proxy
Enable the ‘Use system proxy’ (4) option (toggled on by default). Postman will use the proxy server settings from your operating system.
Step 5: Enable Proxy Authentication
If your proxy server requires a username and password, check the ‘This proxy requires authentication’ (5) box and enter your proxy credentials (6). Click the ‘Save and Restart Postman’ (7) button to save your configuration.
Set Up Custom Proxy Settings in Postman
Alternatively, you can configure Postman to use custom proxy server settings that are restricted to the app. Just as before, we’ll need to repeat steps 1 to 3 from the previous instructions to open the Proxy tab in Postman settings.
Step 1: Disable System Proxy Usage
If needed, disable the ‘Use system proxy’ (1) option.
Step 2: Enable Custom Proxy Settings
Toggle the ‘Use custom proxy configuration’ (2) option to enable custom proxy settings.
Step 3: Configure the Proxy Type
Postman only supports HTTP and HTTPS proxies , so make sure to select the correct protocol (3) next to the ‘Proxy type’ option. If you’re using IPRoyal proxies, you can leave both active, just make sure to select HTTP/HTTPS as the protocol in the IPRoyal dashboard.
Step 4: Input the Proxy Details
Enter the proxy server IP and proxy port (4). If your proxy requires authentication, enable the ‘Proxy auth’ (5) option.
Step 5: Add Proxy Credentials
Enter the proxy credentials under ‘Username’ and ‘Password’ (6).
Step 6: Enable Proxy Bypass
If you don’t want Postman to use the proxy for specific requests, add these URLs or IPs to the box (7) in the ‘Proxy bypass’ section.
Troubleshooting Postman Proxy Issues
Configuring API requests to go through proxies in Postman isn’t enough. There are many errors related to proxies and Postman setup in general. We cover the most common issues below.
407 Proxy Authentication Required
This 407 error indicates that the proxy credentials are missing or invalid. To resolve it, check your Postman credentials under custom proxy settings, depending on how you configured your proxy. In some cases, firewalls and network interference might also be a cause.
Connection Refused Error
In Postman, a connection refused (ECONNREFUSED) error means your request never reaches the API, as your operating system or the server actively rejects it. It’s familiar with misconfigured or missing proxy settings, and when firewalls and other security measures filter the traffic.
Timeout Errors in Postman
Timeout errors (ETIMEDOUT) signal that the request took too long to complete, so the connection was closed before the response arrived. Postman’s timeout settings are often around 30 seconds, so slow APIs, network issues, or proxy problems can cause timeout issues. Changing Postman’s timeout setting is often the first step of troubleshooting.
SSL Errors With HTTPS Proxies
SSL errors with HTTPS proxies are related to certificates between Postman and the proxy or the proxy and the target HTTPS server. Such errors are caused by broken certificate chains, hostname mismatch, expired certificates, and other issues preventing TLS handshakes. Resolution involves verifying certificate details to fix any misconfigurations and adjusting Postman settings.
Best Practices for Optimal Experience
There are a few additional steps you can implement to ensure proxies work with Postman smoothly.
- Double-check proxy authentication. If your proxy server requires it, set proxy credentials either in Postman’s settings or within your OS system configuration.
- Adjust timeout settings. Go to ‘Settings’, then ‘General’, and increase the ‘Request timeout’ value to prevent premature timeouts.
- Use environment-specific proxy settings. If you frequently switch between different proxies when sending requests, it’s a good idea to use environment-specific proxy settings to store different proxy configurations in Postman.
- Test connectivity without the proxy server. Before configuring the proxy, verify that Postman can connect to the API first. This will help you isolate issues if errors occur after the configuration.
Advanced Use Cases for Postman Proxy
To take things up a notch, you can set up proxies in different locations by creating environment variables like proxy_ip, proxy_port, proxy_username, and proxy_password for each location you are testing.
To streamline this process, integrate your proxies with Postman’s Collection Runner. Simply open the ‘Collection Runner’, select your collection and environment for a specific location, and hit ‘Run’ .
For better proxy management, consider using IPRoyal’s API for enhanced data gathering. You can add the API key in the Authorization tab of your Postman headers to automate proxy management with a list of proxies, allowing you to rotate your data-gathering requests efficiently.
Conclusion
The benefits of configuring proxy servers with the Postman app outweigh the hassle of setting it up. Understanding the basic steps and key issues you might encounter will enable advanced use cases, such as using proxies in multiple locations by creating environment variables, while creating and managing APIs.
FAQ
Does Postman support SOCKS5 proxies?
Yes, Postman supports SOCKS5 proxies, but it still sends HTTP and HTTPS requests. Postman is fundamentally an API client for HTTP/HTTPS, so it cannot process any non-HTTP requests, but SOCKS5 proxies will still work. You can configure them in Postman settings by enabling custom proxies and selecting SOCKS5/SOCKS5H when entering server details.
Can I rotate proxies in Postman?
Postman doesn’t have proxy rotation options natively, but there are a few workarounds. The easiest is to simply use rotating proxies, where the rotation is implemented from the provider’s side. You can also define different environments for different proxies and switch them manually, or run collections with Newman multiple times while changing settings between runs.
Why does Postman ignore my proxy settings?
There can be several reasons why Postman ignores your settings, but generally, it happens when something else is bypassing or overriding your proxy setup. The most common reasons are the operating system’s environmental variables, a misconfigured proxy (wrong auth settings, for example), or other software using the same port Postman uses to connect to the proxy.
Can I use Postman behind a corporate firewall?
Yes, you can, and in many enterprise environments, this is expected of developers. Postman often doesn’t work right away, and additional configuration and auth settings will be needed. As such, some users think Postman cannot be used with corporate firewalls, but it just needs to be set correctly.
Is proxy authentication different from API authentication?
Yes, these are different things in Postman settings. Proxy auth is how Postman proves its identity to the proxy server sitting between Postman and the internet. API auth is how Postman proves its identity to the API server you’re actually calling. One lets you connect to the network intermediary, and the other to the target API.
