A cryptic “400 Bad Request” error appearing on your site can be frustrating. A 400 bad request error occurs when a browser sends a request to a web server that the server cannot understand or process correctly. The kitchen doesn’t know how to make your request and has to send back a message saying, “We can’t understand or process this order.”In Google Chrome, a 400 error code page looks like this:In Safari it looks like this:Similar to the way it looks in Firefox:There are many different messages servers use to indicate a 400 error code, including:400 Bad RequestHTTP 400 Bad RequestHTTP Status 400—Bad Request400 Bad Request ErrorHTTP Error 400Bad Request: Error 400HTTP Error 400—Bad RequestLet’s explore the common causes of 400 bad request errors and how to fix them. How to Fix File Size ErrorsTo fix this 400 error, you need to reduce the file size below the website’s size restriction before trying to upload it again. If you’re still getting a 400 bad request error, the issue is server-side and out of your control.