How to Test Your WordPress Website for PHP 7.x Compatibility

There are a number of benefits to running your WordPress website on a recent version of PHP. Among the most noticeable perks is the massive increase in speed. PHP 7.3 runs about three times as many requests per second when compared with PHP 5.6. While performance is important, there is something even more concerning. Both PHP 5.6 and 7.0 reached their end-of-life at the end of 2018. That means neither version is receiving crucial security fixes. Therefore, the longer you remain on one of these non-supported versions, the more potential there is for something bad to happen.
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Also of note is that WordPress is currently recommending that your web server run PHP 7.3 and is making plans to drop support for anything lower than PHP 5.6. But in this case, running at the bare minimum isn’t good enough.
So, if you’re utilizing an outdated version of PHP, it’s time to get up-to-speed. But before you upgrade, it’s important to test your site to ensure that it will continue running smoothly afterwards.
Let’s have a look at some considerations and testing methods
Source: https://managewp.org/articles/18338/how-to-test-your-wordpress-website-for-php-7-x-compatibility

source https://williechiu40.wordpress.com/2019/01/28/how-to-test-your-wordpress-website-for-php-7-x-compatibility/