How to check PHP version

Newer PHP versions come with more features and improvements while deprecating some obsolete features. Old PHP codes might not work with more recent PHP versions and vice versa. It is, therefore, essential to use the correct PHP version for your code.

You can check the PHP version on your system by running the php command from the command line. There are also some PHP functions that you can use in your code to get the PHP version during runtime.

1. Run php -v from the command line.

   $ php -v
   PHP 7.4.3 (cli) (built: May 26 2020 12:24:22) ( NTS )
   Copyright (c) The PHP Group
   Zend Engine v3.4.0, Copyright (c) Zend Technologies
       with Zend OPcache v7.4.3, Copyright (c), by Zend Technologies

2. Run php -i from the command line.

   $ php -i | grep "PHP Version"
   PHP Version => 7.4.3
   PHP Version => 7.4.3

3. Print PHP_VERSION_ID from PHP script.

   <?php 
   	echo PHP_VERSION_ID;
   	//Sample output: 70403
   ?>

4. Print phpversion() output from PHP script.

   <?php 
   	echo phpversion();
   	//Sample output: 7.4.3
   ?>

5. View from phpinfo() output.

   <?php 
   	phpinfo();
   ?>

   

6. Query your package manager where the PHP packages are installed from.

   $ apt show php
   Package: php
   Version: 2:7.4+75
   Priority: optional
   Section: php
   Source: php-defaults (75)
   Origin: Ubuntu
   Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>
   Original-Maintainer: Debian PHP Maintainers <team+pkg-php@tracker.debian.org>
   Bugs: https://bugs.launchpad.net/ubuntu/+filebug
   Installed-Size: 13.3 kB
   Depends: php7.4
   Download-Size: 2,712 B
   APT-Sources: http://jp.archive.ubuntu.com/ubuntu focal/main amd64 Packages
   Description: server-side, HTML-embedded scripting language (default)
    PHP (recursive acronym for PHP: Hypertext Preprocessor) is a widely-used
    open source general-purpose scripting language that is especially suited
    for web development and can be embedded into HTML.
    .
    This package is a dependency package, which depends on latest stable
    PHP version (currently 7.4).

   Package manager query comand for different operating systems and distributions:

   Platform	Command
   homebrew	$ brew list --versions php
   Debian, Ubuntu	$ apt show php
   CentOS, RedHat, Fedora	$ dnf info httpd