504 Error Code Explained: Why Does a Page Load Slowly?
Elsa Ingrid Johansson
2026-07-31 16:00
Have you ever opened a website and found that the page keeps loading for a long time before showing a 504 Gateway Timeout error?Many users assume the problem comes from their browser, computer, or internet connection. However, in most cases, a 504 error code is not caused by your device. Your browser and network only send the request, while the waiting and timeout process usually happens between different website services.
So, where exactly does a 504 error code happen? To understand it, we need to look at the complete journey of a web request.
When you visit a website, your request usually does not go directly to the final server. Instead, it passes through several steps.First, the client, which is your browser, sends a request to access a webpage.Then, the request reaches a gateway or intermediate server, which acts as a bridge between the user and the website’s backend. It receives the request and forwards it to the origin server.The origin server is where the actual processing happens. It handles application logic, retrieves data from databases, and generates the response before sending it back through the gateway to your browser.
A 504 error code occurs during the process when the gateway is waiting for a response from the origin server.The gateway usually has a set waiting time, often ranging from a few seconds to several dozen seconds. After forwarding the request, it starts counting. If the origin server responds within the allowed time, everything works normally.However, if the origin server takes too long to respond, the gateway stops waiting and returns a 504 Gateway Timeout error to the user.
Simply put:A 504 error code means the gateway waited too long for the origin server’s response. It is not “unable to find” the server, but “unable to receive a response in time.”
One of the most common causes of a 504 error code is server overload.When a website suddenly receives a large number of visitors, the server may struggle to process all requests at the same time.For example, during major sales events, breaking news, or sudden traffic spikes, server resources can quickly become insufficient. CPU usage may increase, memory resources may become limited, and database connections may be occupied.As requests wait in a queue, some of them may exceed the gateway’s waiting limit, eventually resulting in a 504 error code.
Sometimes the server itself is working normally, but certain operations take too much time.For example, complex database queries involving large amounts of data may require several seconds or even longer to complete. External API requests can also slow down the response if the third-party service is responding slowly.When backend processing takes longer than the allowed timeout period, the gateway may return a 504 error.
Communication between the gateway and the origin server is not always perfect.Problems such as network delays, routing issues, DNS delays, or connection interruptions can prevent the server response from reaching the gateway in time.In these situations, the origin server may still be running normally, but the connection between services is too slow, causing a timeout.
A 502 error means the gateway received a response from the origin server, but the response was invalid.For example, the application may have crashed, returned incorrect data, or generated an unexpected response. The gateway received an answer, but the answer could not be processed correctly.
A 504 error code means the gateway waited for the origin server’s response but did not receive it within the allowed time.A simple way to understand the difference:502 means the server responded incorrectly.504 means the server responded too slowly.
A 522 error is commonly seen on websites using services such as Cloudflare.It usually means the connection between the gateway and the origin server failed during the connection stage. In other words, the gateway could not successfully establish a connection with the server.A 504 error usually happens after the connection has already been established and the gateway is waiting for the server’s response.
A 524 error also appears in CDN-related situations.It means the gateway successfully connected to the origin server, but the server took too long to process the request.A simple way to imagine it:The phone call was connected, and the other person heard your request, but the response took too long. Eventually, the system ended the call.
| Error Code | Meaning |
| 502 | The origin server responded, but the response was invalid |
| 504 | The origin server did not respond in time |
| 522 | The gateway could not connect to the origin server |
| 524 | The connection was established, but processing took too long |
If you occasionally encounter a 504 Gateway Timeout while browsing, you can try the following steps:
First, wait briefly and refresh the page once. Sometimes a 504 error is caused by temporary traffic congestion, and a new request may work after the situation improves.You can also check your network connection. Switching from WiFi to mobile data or restarting your router can help confirm whether the problem is related to your local connection.
However, be careful when dealing with pages involving payments, orders, or form submissions.Do not repeatedly refresh or submit the same request. The first request may have already been processed by the server, but the response failed to return in time. Submitting again could create duplicate actions.
If the problem continues after waiting, it is usually a server-side issue that requires the website owner to resolve.
For website operators, a 504 error code usually means the server needs further investigation.
First, check the status of the origin server. Review application logs and error logs to see whether there are crashes, failed processes, or slow requests.Next, check server resources, including CPU usage, memory consumption, and database performance. If resources are insufficient, temporarily increasing server capacity may help reduce pressure.You should also review timeout settings. For operations that naturally require more time, such as large report generation or data exports, increasing timeout limits may provide temporary relief.
However, increasing timeout settings only delays the problem. It does not solve the underlying performance issue.The long-term solution is improving backend efficiency, reducing slow operations, optimizing database queries, and making application processes respond faster.At the same time, check the network connection between the gateway and origin server to ensure stable communication.
“Gateway” refers to the intermediate server that forwards requests, while “Timeout” means the waiting time has expired.Together, 504 Gateway Timeout means the gateway forwarded a request to the origin server but did not receive a response in time.In simple terms, the backend service responded too slowly.
Sometimes.If the error is caused by temporary network delays or short-term server congestion, refreshing once may solve the problem.However, if the origin server is continuously overloaded or the application is stuck, refreshing repeatedly will not help.
Not necessarily.Although traffic attacks can overload servers and trigger a 504 error, many cases are caused by normal issues such as sudden traffic increases, slow applications, or insufficient server resources.A 504 error itself does not directly indicate a security problem.
Today, users expect websites to respond instantly. When a page keeps loading and eventually shows a 504 error code, the experience can be frustrating.
However, the internet relies on many servers working together across different locations, and every connection has its limits. A 504 Gateway Timeout is simply a signal that one part of this process did not respond quickly enough.
For users, understanding what a 504 error means can help avoid unnecessary troubleshooting and repeated actions.
For service providers, every 504 error is a reminder to improve server performance, application efficiency, and network reliability.
A stable access environment also plays an important role in maintaining reliable connections. 1024Proxy provides stable IP services to help users build more reliable network environments and improve data request stability.
A 504 error code is not something to panic about. It is simply a signal that a part of the connection process needs attention and improvement.
