304 Status Code: What It Means and How to Fix It

HomepageSecurityWhat is 304 Status Code and How to Fix It?

Seeing an HTTP 304 Not Modified response? It means your browser is using a cached version of a page because nothing has changed, which helps your site load faster.

This guide explains what a 304 status code is, when it’s just normal caching at work, and when website visitors or site owners and developers might need to troubleshoot it.

What is an HTTP 304 Status Code?

An HTTP 304 Not Modified response tells your browser that a page or file hasn’t changed since your last visit, so it doesn’t need to download it again. Instead of resending the whole resource, the server simply confirms your cached copy is still good. This is normal caching; it’s one of the reasons pages load faster and use less data.

You’ll see 304 responses in a few common places:

Browsers, which store images, scripts, and style sheets so they don’t have to re-fetch them on every visit.
CDNs, which cache content closer to visitors and revalidate it instead of re-downloading from the origin server.
Proxies, which sit between you and a website and reuse cached content when they can.
Website performance tools, which often log 304 responses while auditing how fast a site loads.

How the 304 Status Code Works

You visit a page for the first time, and your browser saves some of its files to help it load faster next time. When you return later, your browser checks whether anything has changed. If not, the server returns an HTTP 304 Not Modified response, and your browser reuses its saved copy instead of downloading everything again.

If the page has changed, the server sends the latest version instead. This relies on caching headers like ETag and Last-Modified.

What is the Difference Between 304 and 200 HTTP Status Codes?

An HTTP 200 and an HTTP 304 both mean the browser and server completed the exchange without errors, but they serve different purposes:

HTTP 200 OK returns the requested resource from the server, such as a webpage, image, or file: The server delivers the content directly to the browser so it can be displayed.
HTTP 304 Not Modified tells the browser to use its cached copy because the resource has not changed since the last request: The browser already holds a current version of the resource, so it skips downloading it again.
HTTP 200 OK includes the full response body containing the requested content: The browser receives the complete webpage, image, or file directly from the server.
HTTP 304 Not Modified only returns response headers and does not resend the resource: Only the response headers are sent, so the browser relies on the copy already stored in its cache.
HTTP 200 OK is typically returned when content is new or has been updated: The browser needs to download the latest version of the resource from the server.
HTTP 304 Not Modified helps improve page load speeds and reduce bandwidth usage by reusing cached content: This avoids unnecessary downloads and reduces data transfer between browser and server, improving overall website performance.

How to Fix 304 Not Modified Issues

Here’s how to troubleshoot 304 issues, whether you’re a visitor or you manage the site.

For Website Visitors

These steps address common browser-side causes, such as outdated cache or interfering extensions.

Clear browser cache and cookies: Your browser may be using an older, cached version of a page, so clearing your cache and cookies forces it to check with the server directly. This also clears out stored site data that can sometimes cause pages to behave unexpectedly. After clearing, reload the page and confirm the latest version appears; if it still looks outdated, the issue likely isn’t on your end.

Disable browser extensions: Some extensions (ad blockers, privacy tools, security add-ons, or VPN and proxy tools) can interfere with how pages load. Disable them, reload the page, then re-enable them one at a time to identify which one (if any) is causing the problem.

Try another browser: If the issue only shows up in one browser, it’s likely tied to that browser’s settings, cache, cookies, or extensions rather than the website itself. Open the same page in a different browser to check; if it loads correctly there, the problem is browser-specific.

For Website Owners and Developers

These steps address website, server, and caching configuration issues that can affect all visitors.

Clear website cache: Even after you update a page, website-level caching can keep serving the old version to visitors. Common sources include your CMS’s own cache, a WordPress caching plugin, server-side caching, or caching built into your hosting plan. Clear each layer that applies to your site, then reload the page to confirm your changes are visible.

Purge CDN cache: If your site uses a content delivery network (CDN), it stores copies of your pages closer to visitors to speed up load times. However, it may also keep serving an older cached copy after you update the page. Purging the CDN cache clears that stored version, so visitors get the latest content.
Review server caching configuration: If 304 responses are causing outdated content to appear, the underlying issue is usually in how your server’s caching is configured. Review your Cache-Control settings, ETag configuration, and Last-Modified headers, along with your server’s caching behaviour and how it integrates with your CDN’s caching rules. Misconfigured settings in any of these areas can cause the server to serve or validate content incorrectly.

Common Causes of an HTTP 304 Not Modified Response

A 304 response can happen for several reasons, none of which point to something broken.

Browser caching behaviour: Browsers store files from pages you’ve visited before, so they load faster next time. If those files haven’t changed, you may see a 304 response instead of a full download.
Server caching configuration: Your web server’s caching settings determine when it issues a 304 response. If it’s configured to treat a page as unchanged, visitors may keep seeing cached content instead of updates.
CDN and cache settings: If you use a CDN, it may serve a cached page copy. When that copy still matches your origin server, you’ll see a 304 response instead of new content.
Website and application caching: Websites and web applications can set their own caching rules to control how content is stored and reused. These rules can lead to a 304 response when nothing has changed.

Frequently Asked Questions

What does 304 code mean?

An HTTP 304 means the page or file you requested hasn’t changed since your last visit, so your browser can use the version it already saved instead of downloading it again.

What does error 304 mean?

Despite the name, a 304 isn’t actually an error. It’s a normal response that tells your browser its cached version of a page is still up to date.

Is 304 a redirect?

Technically, yes; 304 belongs to the HTTP redirection status code family. But unlike a typical redirect such as a 301 or 302, it doesn’t send your browser to a different URL. It simply confirms that the cached version you already have is still current.

What is the difference between HTTP status codes 302 and 304?

A 302 tells your browser to temporarily fetch content from a different URL. A 304 tells your browser nothing needs to be fetched at all; what it already has is still good.

Is a 304 status code bad for SEO?

No. A 304 response is a normal part of caching and doesn’t hurt your SEO on its own. Issues only come up if your caching is misconfigured, and visitors or search engines end up seeing outdated content.

How do I stop getting 304 responses?

You generally don’t want to. 304 responses mean your caching is working as intended. If you’re seeing outdated content instead of expected updates, clearing the relevant cache (browser, CMS, or CDN) is the right fix, rather than disabling 304 responses, which would slow your site down.

304 Not Modified: Nothing to Fix, Unless You Need To

A 304 Not Modified response isn’t something to worry about, but it’s your site’s caching doing exactly what it’s meant to do, helping pages load faster for your visitors. If you ever run into outdated content instead, you now have a clear path to fix it: start with the simple checks if you’re a visitor, or work through your caching layers if you manage the site.

If you’re managing hosting and caching for your own site, Vodien’s hosting and CDN plans include built-in caching tools that can make steps like these easier to handle.