PHP Date display as time ago

There is a function for that: human_time_diff(). Use it like so: (U because we want the unix timestamp)

<?php echo human_time_diff( get_the_time('U') ); ?>

If you want additional text, you can use the following

<?php printf (esc_html__('%s ago', 'yourlanguageslug'), human_time_diff(get_the_time('U'))); ?>

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