How to Change PHP Settings from the Command Line

What are PHP settings?

PHP is a language that runs many websites. Its settings control things like how much memory a script can use, or how big an upload can be. They live in a file called php.ini. The command line is a text window where you type commands instead of clicking.

Step 1: Connect

1. Open a terminal. On Windows 10 or later, you can use PowerShell.
2. Connect with SSH. SSH is a safe way to control a server from far away.

ssh username@your-server-address

Use the details from your welcome email.

Step 2: See the current settings

php -i | grep memory_limit

This shows the current memory limit. Change memory_limit to any other setting name.

php --ini

This shows which php.ini files PHP reads.

The command line PHP may use a different file than your website does. Check the web value with a page that runs phpinfo(). Delete that page afterwards.

Step 3: Change a setting

1. Copy the file as a backup.

cp php.ini php.ini.bak

This keeps a safe copy.

2. Open the file in a text editor.

nano php.ini

This opens the file in nano, an easy editor.

3. Find the line to change, for example the following.

memory_limit = 256M
upload_max_filesize = 64M
post_max_size = 64M
max_execution_time = 300

Edit the numbers to what you need. Lines starting with a semicolon are comments and are ignored.

4. Press Ctrl and O to save. Press Enter. Then press Ctrl and X to leave.
5. Restart the web service so the change takes effect. On a VPS with root, the command is often this.

systemctl restart php-fpm

This restarts PHP. The service name differs by system, for example apache2 or php8.2-fpm.

Change a setting for one run only

php -d memory_limit=512M script.php

This runs one script with a bigger memory limit. Nothing is saved.

On shared hosting

You may not be able to edit the main file. Look in your control panel for a PHP settings tool, or ask support in a ticket.

Quick recap

• PHP settings live in php.ini.
• Use php --ini and php -i to look.
• Back up, edit, save and restart the service.
• Use php -d for a one-time change.