Choosing your PHP version and adding extensions

Choosing your PHP version and adding extensions

What you'll learn: what PHP versions are, when to change yours, and how to enable extra PHP features your app needs.

What's a PHP version?

PHP is the programming language WordPress (and many other apps) is written in. New versions come out every year — they're faster and more secure than old ones, but sometimes a plugin written for an older version doesn't work on the newest one.

You can pick which PHP version your site uses, per domain.

Which version should I pick?

  • The latest supported is usually the right answer. As of 2026, that's PHP 8.3 or 8.4. Faster, safer, supported with security fixes.
  • PHP 8.1 or 8.2 is fine if a plugin you depend on hasn't been updated yet.
  • PHP 7.x is no longer secure. If you're on it, plan to upgrade.

WordPress itself supports current PHP versions out of the box. Plugin compatibility is the more common concern.

How to change your PHP version

Sidebar → Sites → Domains → click your domain → PHP (or PHP version).

[screenshot here: PHP version selector]

  1. Pick a version from the dropdown.
  2. Click Save.

The change takes effect immediately. Visit your site to make sure it still works.

If your site breaks, switch back to the previous version using the same dropdown.

How to add a PHP extension

PHP extensions add specific features — like image processing (gd, imagick), reading XML, talking to certain databases, or speeding things up (opcache).

Sidebar → Sites → Domains → click your domain → PHP extensions.

You'll see a list of available extensions with checkboxes:

  1. Tick the ones you need.
  2. Click Save.

Common ones you might need:

  • gd or imagick — for resizing images
  • mbstring — for handling text in non-Latin alphabets (commonly required by WordPress)
  • zip — for zip file support
  • curl — for talking to other websites and APIs
  • opcache — speeds up PHP (turn this on)

If you're not sure which ones you need, your app's docs will say.

Custom PHP settings (php.ini)

For advanced settings — like raising the memory limit or upload size — there's usually a PHP settings or php.ini page. Common settings to adjust:

  • memory_limit — 256M is generous for WordPress
  • upload_max_filesize and post_max_size — for big media uploads
  • max_execution_time — how long a single PHP script can run

Change one thing at a time, save, and test.

Tips

  • Test in staging first. If your site is important, change PHP version on a staging copy first, confirm it works, then change live.
  • Don't enable extensions you don't need. More extensions = slightly more memory used by every request.
  • Keep WordPress and plugins updated. Old code is often the reason a new PHP version breaks something — and the fix is usually as simple as updating the plugin.

If something goes wrong

  • Site shows a "white screen of death" after switching PHP versions — switch back to the old version. Then update plugins/themes one at a time, then try the new version again.
  • Extension doesn't appear in the list — your hosting plan might not include it. Ask your provider.
  • Memory limit changes don't seem to take effect — make sure you saved on the right domain, and clear any caching plugins.

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