Add Published and Modified Date Meta Tags to Joomla

Google, Facebook and LinkedIn read two meta tags to learn when an article was published and when it last changed: article:published_time and article:modified_time. A fresh date can earn a "2 days ago" label in search results and tells the networks to refresh a shared card. Joomla keeps both dates for every article but writes neither into the head. You can add the two tags with one snippet in Code Snippets, as two lines of HTML or as a PHP snippet that adds the time of day.

Using an HTML snippet

This is the basic version: two meta tags, filled in by smart tags when the page renders. It writes the dates without the time, like 2026-10-16, which is all the networks need for a card, and it covers single article pages.

1. Install Code Snippets if it isn't installed already.
2. Log into your Joomla backend.
3. Go to Components → Tassos Code Snippets.
4. Click New.
5. Enter a title, for example Article date tags.
6. Set Code Type to HTML.
7. Set Insertion Method to Auto-Insert Locations.
8. Set Location to Site Header.

9. Paste this code into the editor:

   <meta property="article:published_time" content="{tcs article.publish_up --filter=re:\s.*}">
   <meta property="article:modified_time" content="{tcs article.modified --filter=re:\s.*}">

10. Open the Conditional Logic tab:

    • Set Display on to Selected Pages.
    • Click New Condition Set.
    • Click Select Condition and choose Content View.
    • Select Single Article.
11. Click Save & Close.

The {tcs article.publish_up} smart tag prints the article's Start Publishing date and {tcs article.modified} its modified date, both as 2026-10-16 15:45:00. The --filter option removes the space and everything after it, which leaves the date in the form the networks read.

The condition matters. Outside a single article page the article smart tags print nothing, and an empty date tag is worse than none. The Content View condition is part of Code Snippets Pro. With the free version, use the PHP snippet below, which needs no condition.

Being the basic version, it has one limit: Joomla stores dates in UTC, and the tag prints the UTC date. An article published at 01:00 in Athens carries the day before. If that matters to you, or you want the time of day in the tags, use the PHP version.

Using a PHP snippet

Use this method if you want more flexibility. It writes the full date and time with your site's time zone offset, as 2026-10-01T11:00:00+03:00, falls back to the creation date when Start Publishing is empty, and needs no condition, because it checks for an article page itself.

use Joomla\CMS\Document\HtmlDocument;
use Joomla\CMS\Factory;
use Joomla\CMS\HTML\HTMLHelper;
use Joomla\Database\DatabaseInterface;
use Joomla\Database\ParameterType;

$app = Factory::getApplication();

$app->registerEvent('onBeforeCompileHead', function () use ($app) {
    $doc = $app->getDocument();

    if (!($doc instanceof HtmlDocument))
    {
        return;
    }

    $input = $app->getInput();

    $isArticle = $input->getCmd('option') === 'com_content'
        && $input->getCmd('view') === 'article';

    if (!$isArticle)
    {
        return;
    }

    $id    = $input->getInt('id');
    $db    = Factory::getContainer()->get(DatabaseInterface::class);
    $query = $db->createQuery()
        ->select($db->quoteName(['created', 'publish_up', 'modified']))
        ->from($db->quoteName('#__content'))
        ->where($db->quoteName('id') . ' = :id')
        ->bind(':id', $id, ParameterType::INTEGER);
    $article = $db->setQuery($query)->loadObject();

    if (!$article)
    {
        return;
    }

    // Joomla stores dates in UTC. The 'c' format writes them in the site's
    // time zone, as 2026-10-17T14:30:00+03:00.
    $published = $article->publish_up ?: $article->created;

    $published = HTMLHelper::_('date', $published, 'c');
    $modified  = HTMLHelper::_('date', $article->modified, 'c');

    $doc->setMetaData('article:published_time', $published, 'property');
    $doc->setMetaData('article:modified_time', $modified, 'property');
});

There is nothing to change. The time zone comes from Website Time Zone in your Global Configuration, so a site set to Europe/Athens writes 2026-10-01T11:00:00+03:00 for an article published at 08:00 UTC.

1. Install Code Snippets if it isn't installed already.
2. Log into your Joomla backend.
3. Go to Components → Tassos Code Snippets.
4. Click New.
5. Enter a title, for example Article date tags.
6. Set Code Type to PHP.
7. Set Insertion Method to Auto-Insert Locations.
8. Set Location to On Page Load.
9. Paste the code above into the editor.
10. Click Save & Close.

Use one snippet or the other, never both.

Check that it works

1. Open any article on your site.
2. View the page source and search for article:.

Two meta tags carry the article's dates: 2026-10-16 with the HTML snippet, 2026-10-16T18:45:00+03:00 with the PHP one. An article that was never edited shows the same value in both, because Joomla sets the modified date when the article is created. The homepage, category pages and feeds have no such tags.

These tags belong next to the Open Graph tags that give a shared link its title and image. See Add Open Graph and Twitter Card Tags to Joomla for those. To show the modified date to readers on the page itself, see Display the Last Modified Date in Joomla Articles. To learn more about the two snippet types, read the HTML snippet docs and the PHP snippet docs.