CompatNav

Getting started

Install CompatNav, choose the PHP version you plan to move to, and run your first scan.

What you need

  • A WordPress site with WordPress 6.0 or newer that runs PHP 7.4 or newer.
  • An administrator account. On a multisite network, only super admins can use CompatNav.

Your site still runs PHP 7.2 or 7.3? Ask your host to move it to PHP 7.4 first (current WordPress needs PHP 7.4 too). Then use CompatNav to prepare the move to PHP 8.

1. Install the plugin

  1. In your WordPress admin, go to Plugins → Add New Plugin.
  2. Search for CompatNav, click Install Now, then Activate.

You can also download the zip file from the plugin page on wordpress.org and upload it under Plugins → Add New Plugin → Upload Plugin.

2. Choose the PHP version you plan to move to

Go to Tools → CompatNav. Next to Check readiness for, choose the PHP version you plan to upgrade to. CompatNav checks upgrades to PHP 8.0, 8.1, 8.2, 8.3, 8.4 and 8.5.

Not sure which one? Ask your host which PHP versions they offer, or look in your hosting control panel. Choosing the newest version your host offers gives you the longest time before the next upgrade.

3. Run the scan

Click Start scan. A progress bar shows how many files have been checked.

  • You can Pause, Resume or Cancel scan at any time.
  • Keep the page open while the scan runs. If you leave the page, the scan pauses until you come back.
  • A file too heavy for your server’s memory is skipped and listed, and the scan continues.

How long it takes depends on how much code your plugins and themes contain. On a test site with 17 plugins and themes (8,374 PHP files), a full scan took about 70 seconds.

When the scan is complete, the report appears on the same page. Later scans use the button Start new scan; a new scan replaces the report only when it has finished.

What CompatNav compares

CompatNav compares the PHP version your site runs today with the one you chose, and reports only what changes between the two. Code that is fine on both versions is not reported.

Scan settings

Under Scan settings there is one option: Skip bundled libraries (vendor folders). Leave it off. Outdated bundled libraries are a common reason sites break after a PHP upgrade. The setting is saved when you start a scan.

Next: Reading the report.