HTTP Error 431: What It Means & How to Fix It

HTTP error 431 in Google Chrome means the request headers you sent to a website are too large for the server to process. The fix is usually to clear your browser cookies and site data for that specific site, or to remove problematic browser extensions. Below is a complete breakdown of why this happens and every practical step you can take to resolve it.

What Exactly Is HTTP Error 431?

Error 431 is a standard HTTP status code defined in RFC 6585 as “Request Header Fields Too Large.” When you visit a website, your browser sends a request that includes headers—small pieces of metadata like cookies, user-agent strings, and authorization tokens. If the total size of those headers exceeds the server’s configured limit (often around 8 KB to 16 KB, but varies by server), the server responds with 431 instead of loading the page.

In Chrome, this error usually appears as “Error 431” or “The page isn’t working” with a message about request header fields being too large. It is not a sign that your computer is infected or that the website is down; it is a communication problem between your browser and the server.

Why Do Headers Get Too Large?

The most common cause is an accumulation of cookies. Every time you visit a site, it may set cookies, and Chrome stores them. If a site sets many cookies or a single very large cookie (for example, a tracking or analytics cookie that stores a long string), the combined size can exceed the server’s limit. Other causes include:

Browser extensions that inject extra headers into every request (ad blockers, privacy tools, or SEO extensions).
Corrupted site data from a previous session that keeps getting resent.
A misconfigured website that sets an unusually large cookie or header on its own.
Proxy or VPN services that add their own headers to your requests.

In rare cases, a website’s own code can cause the error for all visitors, but if you can access the site in an incognito window, the problem is almost certainly on your side.

How to Fix Error 431 in Chrome (Step-by-Step)

Start with the simplest fix and work down the list. You do not need to try all of them; stop when the page loads.

Clear cookies and site data for the affected site. Click the padlock icon next to the URL, select “Cookies and site data,” then “Manage on-device site data.” Find the site, click the trash icon, and reload. This removes the oversized cookies while keeping your logins on other sites.
Try incognito mode. Press Ctrl+Shift+N (Windows) or Cmd+Shift+N (Mac). Incognito starts with no cookies or extensions, so if the page loads there, the issue is cookie- or extension-related.
Disable extensions. Go to chrome://extensions, toggle off all extensions, then reload the page. If it works, re-enable them one by one to find the culprit. Pay special attention to ad blockers and privacy tools that modify headers.
Clear all browsing data. If the site-specific fix doesn’t work, go to Settings > Privacy and security > Clear browsing data. Choose “All time” and check “Cookies and other site data” and “Cached images and files.” This is more thorough but will log you out of most sites.
Check your proxy or VPN. Temporarily disable any VPN or proxy extension, then reload. Some services add large headers that push you over the limit.
Reset Chrome settings. As a last resort, go to Settings > Reset and clean up > Restore settings to their original defaults. This disables extensions and clears temporary data without deleting bookmarks or passwords.

What If the Error Persists on All Sites?

If you get 431 on multiple websites, not just one, the problem is likely a browser extension or a corrupted Chrome profile. Try creating a new Chrome user profile (click your avatar > Add > Sign in or continue without an account) and test the site there. If it works, your main profile has a corrupted cache or an extension that affects all requests.

Another possibility is a system-level proxy misconfiguration. On Windows, check Settings > Network & Internet > Proxy; on Mac, check System Settings > Network > Proxies. Make sure “Automatically detect settings” is on and no manual proxy is set unless you intentionally use one.

Is Error 431 a Security Threat?

No. Error 431 is a client-server protocol issue, not a security warning. It does not mean your data was compromised or that the site is malicious. However, if you see 431 on a site you trust, it’s safe to clear cookies and retry. If the site itself is misconfigured, there is nothing you can do except wait for the site owner to fix it. You can verify this by trying the site in a different browser (Firefox, Edge) or on your phone; if it works there, the problem is Chrome-specific.

How to Prevent Error 431 in the Future

Use fewer extensions. Each extension that adds headers increases your request size. Keep only what you need.
Set Chrome to clear cookies on exit. Go to Settings > Privacy and security > Cookies and other site data, and enable “Clear cookies and site data when you close all windows.” This prevents long-term cookie buildup.
Use a dedicated cookie manager. Extensions like EditThisCookie (or manual DevTools) let you inspect and delete oversized cookies before they cause problems.
Update Chrome regularly. While 431 is not a Chrome bug, newer versions handle large headers more gracefully and may reduce the chance of hitting server limits.

Frequently Asked Questions

Does clearing cookies log me out of everything?

Clearing cookies for a single site logs you out of that site only. Clearing all cookies logs you out of every site you use. If you want to avoid re-entering passwords, use the site-specific method first.

Can a website fix 431 on its end?

Yes. The server administrator can increase the max_http_header_size or equivalent setting (in Nginx, Apache, or IIS). If the error happens for everyone, it’s a server-side issue, and you should contact the site owner.

Why does incognito mode work but normal mode doesn’t?

Incognito mode starts with no cookies and no extensions. If the page loads there, the problem is either a cookie that has grown too large or an extension that adds headers. The fix is to clear that site’s data or disable extensions.

Is error 431 the same as error 414?

No. Error 414 means the URL itself is too long, while 431 means the request headers (including cookies) are too large. Both are “too much information” errors, but they have different causes and fixes.

Will a browser update fix this?

Usually not, because 431 is triggered by the server’s limit, not by Chrome. However, updating Chrome can fix underlying cookie-handling bugs that might contribute to oversized headers in rare cases.

Can a mobile browser get error 431?

Yes, but it’s less common because mobile browsers tend to store fewer cookies. If it happens, clear the site data in your mobile browser’s settings or use a private browsing tab.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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