502 Bad Gateway: What Is It? Error Variations, and 11 Effective Ways to Fix the Error

Gaurav Rathore
Gaurav Rathore

Tech Writer

His write-ups blend creativity, personal experience, and tailored technical advice, meeting reader needs effectively.

7 min read

A 502 bad gateway is among the most common errors that people encounter almost every day. There’s no denying that such technical issues are frustrating and require some troubleshooting techniques to vanish from sight.

With this blog, I’ll help you learn more about the error, its causes, and how to fix it easily. 

Quick Answer: A 502 Bad Gateway error is an indication that a web server on the internet has received an invalid response from another server. Think of it as making a phone call, but you’re not able to connect to the person due to some network issue.

What is a 502 Bad Gateway?

A 502 bad gateway error is an HTTPS status code that shows a communication issue between two web servers. So, you’ll receive this error when you visit a website that gets an invalid response from the host server. Apart from this, server overloads, network problems, and configuration issues on the website also cause this error. 

If you come across this error, there’s no need to worry about your device or the internet connection. The 502 error is a server-side issue and only occurs if the gateway server is unable to communicate with the host server. 

What’s the Cause Behind a 502 Bad Gateway Error?

As it is now clear that the error code 502 is only caused by a communication failure between web servers, there are a few more causes behind it. Let’s take a look:

  • Meaningless response: If you receive wrong or incomplete data from the other web server, it will result in a 502 gateway error.
  • Incorrect format: The information fed in is in the wrong language or technical format that the intermediary server is unable to interpret.
  • Server overload: The other server is overloaded with several visitors at a time and is unable to respond at the moment.
  • Network problems: The connection between the two servers is full of glitches.
  • Backend server issues: There can be some issues in the backend configurations of the website. In this case, only a professional web developer can provide a solution.
  • Security software: Some network issues can also be caused by the security software. It happens when the firewall suspects malicious activity and interferes with communication.
  • Temporary glitches: Error 502 Bad Gateway is also caused by some temporary glitches or server hiccups.

That’s it; these are the few reasons behind the 502 error code. 

11 Effective Ways to Fix the 502 Bad Gateway Error

There are several possible causes behind the 502 gateway error, but fortunately, there’s no lack of solutions to get rid of this error efficiently.

1. Reload the page

A quick refresh can sometimes fix the 502 bad gateway error if there’s a temporary glitch or a sudden traffic surge on the website. To refresh the page, press F5 or CTRL + F5 on Windows, and use CMD + R on Mac.

2. Check the URL twice

To err is human, and if you make any typos when entering the URL in the address bar of your browser, you’ll end up receiving the 502 error. So, check the URL twice before you press Enter.

3. Check the site’s status

You may encounter the error if the site is temporarily down or under maintenance. To check if the site is down for everyone, or just for you, you can try online tools like a tool like “Down for everyone or just me.”

4. Clear the browser’s cache

Corrupted and outdated files in your browser’s cache files can also lead to the 502 Bad Gateway error. Hence, you must delete cache files from the browser regularly.

Pro tip: Removing cached files can also delete important browser data including site preferences and useful bookmarks. So, it is better to export browser data first and then import it later. 

5. Open the link in the incognito mode

If the error persists, try to access the site in incognito mode. This often helps in getting rid of the error. In addition, you can open the site on another browser or device.

6. Flush the DNS cache

Unresponsive DNS servers can also cause the 502 bad gateway error. To fix this, you must clear the DNS cache and change the DNS servers if required.

7. Check plugins and themes

Faulty plugins and themes can be the reason behind the 502 error. This happens because of a conflict between poorly coded plugins and themes. To fix this, you must stop all plugins and re-activate them one by one.

8. Disable the extensions

Seems pretty hard to believe, but one of your browser’s extensions can cause the 502 bad gateway error. If that’s the case, you must open the browser in incognito mode, which disables all the extensions.

9. Check your proxy server, VPN, and firewall

Incorrect proxy server,  VPN, or firewall configurations can also cause error 502. It is more common when you manually set up your proxy or VPN connections and end up making mistakes. So, be careful when you’re configuring them.

10. Contact customer support

If all these methods don’t work, you can either try again later or contact customer support for the right solution. The professionals can analyze the problem better and will give you the exact time when the site will be working fine.

11. Increase PHP max_execution_time and max_input_time

There’s a fixed time for a PHP process to load that is called max_execution_time or max_input_time. But when a PHP process takes longer to load than required, it results in a PHP timeout. These values are set under the PHP settings of your web browser, and often the loading time is set to 300 seconds by default. 

So, if the timeout occurs during the migration process, it will result in a 502 error. The only solution to fix this is to contact the customer support of your hosting provider and make the changes to the set values. 

Common Variations of the 502 Bad Gateway Error

Whenever you encounter the 502 error on the web, you’ll notice that it’s just “502 Bad Gateway” written on a simple white page. However, there are some variations of this HTTP status code that you need to be aware of. So, take a look:

  • “502 Service Temporarily Overloaded”
  • “502 Proxy Error”
  • “502 Server Error: The server encountered a temporary error and could not complete your request.”
  • “502. That’s an error.”
  • “502 Bad Gateway Apache”
  • “502 Bad Gateway Cloudflare”
  • “502 Bad Gateway Nginx”
  • “Error 502”
  • “Bad Gateway: The proxy server received an invalid response from an upstream server.”
  • “HTTP 502”
  • “HTTP Error 502 – Bad Gateway”
  • “Temporary Error (502)”

Apart from these variations, you may come across a blank screen with no text on it.

Summing Up

Encountering errors like 502 Bad Gateway are surely annoying, but are not permanent. To get rid of this error, you must find the cause first and then search for the apt solution. 

Nevertheless, you need to pay attention to the URL entered, third-party plugins and themes installed with bad code, and even unoptimized queries to stay away from this error.

FAQs

How do I fix 502 Bad Gateway?

There are multiple methods to fix this error, but clearing the cache is considered the best.

Is 502 Bad Gateway permanent?

If the error is outside of your control, it is 100% temporary. 

How do I stop error 502?

To stop error 502 try reloading the page, checking the site status, trying in incognito mode, clearing your browser cache, checking for DNS issues, checking with your host, and more.

Sources

HTTP 502 – Wikipedia

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