Quick Summary
The "400 Bad Request" error in Chrome indicates that the server cannot understand the request sent by your browser due to a client-side error. This usually means there's an issue with the URL, cookies, or cached data.
Common Causes
- Incorrect URL: The URL you're trying to access is malformed, contains invalid characters, or has syntax errors. This prevents the server from correctly interpreting your request.
- Corrupted Browser Cache and Cookies: Outdated or corrupted data stored in your browser's cache and cookies can conflict with the server's expectations, leading to a 400 error.
- DNS Lookup Issues: Problems with the Domain Name System (DNS) resolution can lead Chrome to request the website from the wrong server, or to not find the server at all. Although less common, improper DNS settings may result in malformed or incorrect requests.
- Large Request Headers: Sometimes, the request headers your browser sends can become too large, surpassing allowed limits on the server-side. This is often due to excessive use of browser extensions or bloated cookies.
Step-by-Step Fixes
Method 1: Double-Check the URL
Step 1: Carefully examine the URL you entered. Look for typos, extra characters, or incorrect syntax.
Step 2: If you copied the URL, ensure that the entire address has been correctly pasted.
Step 3: Try manually entering the URL instead of copying and pasting if the above steps didn't solve the issue.
Method 2: Clear Browser Cache and Cookies
Step 1: In Chrome, click the three vertical dots in the top-right corner and select "More tools" > "Clear browsing data...".
Step 2: Set the time range to "All time".
Step 3: Check the boxes for "Cookies and other site data" and "Cached images and files".
Step 4: Click "Clear data".
Step 5: Restart Chrome and try accessing the website again.
Method 3: Clear Browser Cookies for Specific Website
Step 1: In Chrome, click on the three vertical dots and go to "Settings".
Step 2: Click on "Privacy and security" and then "Cookies and other site data".
Step 3: Click on "See all site data and permissions", search for the specific website, and then clear the cookies.
Step 4: Restart Chrome and try accessing the website again.
Method 4: Flush DNS Cache
Step 1: Open the Command Prompt (Windows) or Terminal (macOS/Linux).
Step 2: Type the following command and press Enter: ipconfig /flushdns (Windows) or sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder (macOS).
Step 3: Restart your browser and try accessing the website again.
Method 5: Disable Browser Extensions
Step 1: In Chrome, type chrome://extensions in the address bar and press Enter.
Step 2: Disable all extensions by toggling the switch next to each one.
Step 3: Refresh the page causing the error. If the error is resolved, re-enable your extensions one by one to identify the culprit.