HTTP 400 Bad Request vs 408 Request Timeout
Both HTTP 400 (Bad Request) and 408 (Request Timeout) belong to the 4xx Client Error category. 400 indicates that the server cannot process the request due to malformed syntax, invalid request message framing, or deceptive request routing. Meanwhile, 408 means that the server timed out waiting for the request. The client did not produce a request within the time the server was prepared to wait.
Description
The server cannot process the request due to malformed syntax, invalid request message framing, or deceptive request routing.
When You See It
When sending malformed JSON, missing required fields, or invalid query parameters.
How to Fix
Check the request body format, validate all required fields, and ensure proper encoding.
Description
The server timed out waiting for the request. The client did not produce a request within the time the server was prepared to wait.
When You See It
When a client takes too long to send the complete request (slow upload, network issues).
How to Fix
Retry the request. Check your network connection. Reduce request payload size.
Key Differences
HTTP 400: The server cannot process the request due to malformed syntax, invalid request message framing, or deceptive request routing.
HTTP 408: The server timed out waiting for the request. The client did not produce a request within the time the server was prepared to wait.
You encounter 400 when when sending malformed JSON, missing required fields, or invalid query parameters.
You encounter 408 when when a client takes too long to send the complete request (slow upload, network issues).
When to Use Which
For 400 (Bad Request): Check the request body format, validate all required fields, and ensure proper encoding. For 408 (Request Timeout): Retry the request. Check your network connection. Reduce request payload size.