Free Online If-Modified-Since HTTP Header Checker

Check your website supports the If-Modified-Since HTTP header used by search engine bots to greatly reduce bandwidth costs and server load.

The If-Modified-Since header allows a web bot to tell your web server the date it last accessed the URL. Your web server can simply respond with a "304 Not Modified" HTTP Header, instead of having to return the entire web page / image.

This saves you money in bandwidth costs. It also shows the search engine that you are bot friendly.

ForBrains have a free to use, online HTTP Header analyser you can use to check your website. The results it shows are both suitable to people with little web knowledge, and those who require the low level information in order to upgrade web server configurations and software. For more information please visit our dedicated page: HTTP Header Analysis or if you already know about HTTP headers you can use the tool directly below:

Checking URL: https://forbrains.co.uk ...

Status: HTTP/1.1 200 OK
Date: Mon, 23 Mar 2026 22:45:52 GMT
Server: Apache
Cache-Control: no-store, no-cache, must-revalidate
Pragma: no-cache
Content-language: en
X-Powered-By: ForBrains WCMS
Expires: Mon, 23 Mar 2026 23:30:00 GMT
Set-Cookie: Array ( [0] => WCMSDT=D; expires=Wed, 22 Apr 2026 22:45:52 GMT; Max-Age=2592000; path=/ [1] => WCMSLT=D; expires=Wed, 22 Apr 2026 22:45:52 GMT; Max-Age=2592000; path=/ [2] => WCMSAC=2624371; expires=Mon, 15 Mar 2027 08:45:52 GMT; Max-Age=30794400; path=/ [3] => PHPSESSID=ocmot75qsp0ih7gc419tn48o8t; path=/ )
Upgrade: h2,h2c
Connection: Upgrade, close
Last-Modified: Mon, 23 Mar 2026 18:00:00 GMT
Vary: Accept-Encoding
Transfer-Encoding: chunked
Content-Type: text/html; charset=UTF-8

Results

1. The value for Cache-Control is telling web-browsers not to cache this page. Ideal if you have dynamic content; a waste of bandwidth if you have pages that do not frequently change. Dangerous is using without checking for MSIE in the UserAgent due to how Internet Explorer handles downloads.
2. The value for Pragma is telling web-browsers not to cache this page. Ideal if you have dynamic content; a waste of bandwidth if you have pages that do not frequently change. Dangerous is using without checking for MSIE in the UserAgent due to how Internet Explorer handles downloads.
3. Great to see you have a Content-Language entry. This tells the search engine and web-browser that your web-page is in "en".
4. Great to see you have a Expires entry. Make sure that this is set to the past if you want the web-browser to grab a fresh copy each time instead of using it's cache. Set to the future if you want to save bandwidth and tell the web-browser / search engine that the content of this page in the cache can be updated later.
5. Great to see you have a Last-Modified entry. Make sure that this is sometime in the past (when you last updated the page).

Analyse URL: (include "http://" or "http://")