304 Not Modified

What is 304 Not Modified?

The 304 Not Modified status code is one of the lesser used aspects of SEO but still plays an important role in website performance and deserves attention if you’re focusing on getting to grips with web development.

When a browser or crawler has already downloaded a page and visits again, it may ask the server whether anything has changed since the last arrival. If nothing’s different, the server responds with a 304, which indicates that the current version of the site is the cached copy, so there’s no need to resend the whole page.

As a result, 304s can be useful because they can make browsing more efficient for users. Resending identical pages wastes bandwidth and time for all involved. Instead, the server can let the browser reuse what’s already been stored to make repeat visits faster for returning customers.

This can also improve the efficiency of search engine crawlers like Googlebot, and can help them to focus their efforts towards different pages that have either recently been modified or are in need of attention.

How do I Use 304s?

In most cases, 304s aren’t something that you manage directly. Instead, they are handled automatically by your server and caching setup based on headers like Last-Modified and ETag.

You can encounter the code sometimes if you’re looking at server logs or are working on some technical SEO. If you see lots of 304s when exploring your pages, this can typically be regarded as a good sign, and shows that your site caching is working as intended.

So, what should you look out for? 304s become more relevant when it comes to troubleshooting. If your pages are throwing up 304s when they’ve recently been updated, it might mean that crawlers and browsers are using old content, which can harm your Google rankings and slow down how quickly changes are reflected in search results.

If this is happening, it usually means that there’s a configuration error in caching headers rather than a result of user error.

Generally speaking, a 304 is a normal and helpful response that helps to keep your website efficient by preventing browsers from downloading pages in a way that isn’t needed.

This is usually a process that works in the background, with little need for intervention. But keeping on top of 304 challenges can be a good way to ensure that you quickly troubleshoot problems as they occur, or why content isn’t showing up on search engine results as you expected.