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How can you detect when somebody else's web page was last updated (or was changed)?

Vadim Kotov
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Gaurav
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4 Answers4

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01. Open the page for which you want to get the information.

02. Clear the address bar [where you type the address of the sites]:

and type or copy/paste from below:

javascript:alert(document.lastModified)

03. Press Enter or Go button.

Wassim AZIRAR
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    This works *only* for static web pages. Although, many (most?) small websites are still using static pages, this will definitely not work on major sites such as microsoft.com or google.com. – Andreas Rejbrand Jul 06 '10 at 19:42
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    Yes, it will return the SysDate. – Wassim AZIRAR Jul 06 '10 at 20:01
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    As for today , If you are you using Chrome browser (Google) your suggestion/solution won't work since the address bar has a new meaning - it actualy search in google engine! – john Smith May 18 '14 at 10:59
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    @johnSmith You can create a bookmark with as address the javascript. – Didii Jul 15 '14 at 07:25
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    This works best if you go developer tools (F12->console) and paste the above code and hit enter. But like Andreas mentioned, it only works for static pages and not dynamically generated websites – Kiong Mar 04 '15 at 02:59
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The last changed time comes with the assumption that the web server provides accurate information. Dynamically generated pages will likely return the time the page was viewed. However, static pages are expected to reflect actual file modification time.

This is propagated through the HTTP header Last-Modified. The Javascript trick by AZIRAR is clever and will display this value. Also, in Firefox going to Tools->Page Info will also display in the "Modified" field.

spoulson
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7

In general, there is no way to know when something on another site has been changed. If the site offers an RSS feed, you should try that. If the site does not offer an RSS feed (or if the RSS feed doesn't include the information you're looking for), then you have to scrape and compare.

JSBձոգչ
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5

Take a look at archive.org

You can find almost everything about the past of a website there.

falstro
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Zararsiz
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  • Despite the down votes this is probably the best approach - you could compare cached versions on archive.org to find roughly when the webpage was last updated. – hoju Oct 09 '15 at 19:17
  • Yes this was useful, as it showed me how often http://qmethod.org/about had been updated. Thanks. – Ahmad Nov 03 '15 at 20:32
  • I concur. This is the best answer. – mycowan Jan 12 '16 at 07:08
  • I also agree that this is the most reliable method. It only works for pages that have been archived, but that includes a lot (70 PB & 514B pages as of Dec 2020 according to Wikipedia). The Wayback Machine extension is available for most browsers, making it easy to browse the archived versions of any page. – Trutane Dec 22 '21 at 21:31