What Is a 504 Gateway Timeout Error?

A 504 Gateway Timeout error is very similar to a 502 Bad Gateway. It's a server-to-server communication error. The key difference is the *reason* for the failure.

What's the Difference: 502 vs. 504?

• A 502 Bad Gateway error means the gateway server received an *invalid* response (a broken message) from the origin server.
• A 504 Gateway Timeout error means the gateway server received *no response at all* in time. It waited and waited, and the origin server was too slow, so it "timed out."

This error is almost always caused by an overloaded or slow origin server.

How to Fix 504 Errors (For Site Owners)

1. Check for Server Overload

Your server is likely overwhelmed. It's too busy to answer the gateway's request in time.

• How to fix: Check your hosting plan's CPU/RAM usage. If you are constantly hitting limits, upgrade your hosting plan.

2. Look for Long-Running Scripts

You might have a complex process, a "heavy" plugin, or a poorly optimized database query taking too long to execute.

• How to fix: Install a monitoring plugin to see which database queries or scripts are taking the most time, then optimize or delete them.

3. Contact Your Host

If you can't find the source of the slowdown, it's time to contact your host. They can analyze the server performance from their end.