How do I know when a web page was updated?

Question

How can you detect when any other web page has been updated (or has been changed)?

Answer 1

The last modified time is based on the assumption that the web server provides accurate information. Dynamically generated pages are likely to return pageview time. However, static pages are expected to reflect the actual file modification time.

This is distributed via the Last-Modified HTTP header. AZIRAR's Javascript trick is smart and will display this value. In addition, in Firefox, the menu "Tools" → "Page" will also be displayed in the "Modified" field.

Answer 2

01. Open the page for which you want information.

02. Clear the address bar [when entering the site address]:

and type or copy / paste below:

 javascript:alert(document.lastModified) 

03. Press the Enter or Go button.

Answer 3

In general, there is no way to find out when something has changed on another site. If the site offers an RSS feed, you should try this. If the site does not offer an RSS feed (or if the RSS feed does not include the information you are looking for), you should clear and compare.

Answer 4

Take a look at archive.org

You can find almost everything about the past website.