Option 1: Plugin
The Regenerate Thumbnails Plug-in.
This option is usualy slower - and some hosting providers might confuse it for a malicious attach and block the IP.
Option 2: WP-CLI
WP-CLI is the command line interface for WordPress/ClassicPress.
Installation
From the WP-CLI Guide
curl -O https://raw.githubusercontent.com/wp-cli/builds/gh-pages/phar/wp-cli.phar
Run --info
from your WP root directory, to check if it works:
php wp-cli.phar --info
If you get a json_encode
error, it means your PHP version is not compatible with WP-CLI.
PHP 7 was the default on one server, it did not work.
Check for other PHP versions
which php
// /usr/bin/php
ls /usr/bin/php*
// php80 php81 php82 php83
Let's use the latest verson of PHP.
php83 wp-cli.phar --info
Regenerating
Regenerate all images, without confirmation.
php83 wp-cli.phar media regenerate --yes
Regenerate thumbnails only.
$ php83 wp-cli.phar media regenerate --image_size=thumbnail
More options for regenerating images with WP-CLI:
# Regenerate thumbnails for given attachment IDs.
php83 wp-cli.phar media regenerate 123 124 125
# Re-generate all thumbnails that have IDs between 100 and 200.
seq 100 200 | xargs php83 wp-cli.phar media regenerate
# Re-generate all thumbnails that have IDs between 100 and 200.
seq 100 200 | xargs php83 wp-cli.phar media regenerate
# Re-generate all thumbnails that have IDs between 100 and 200, only thumbnails
seq 100 200 | xargs php83 wp-cli.phar media regenerate --image_size=thumbnail
#### Error
`Error: Error establishing a database connection.`
When working on _localhost_, use `127.0.0.1` instead of `localhost` in wp.config
```php
define( 'DB_HOST', '127.0.0.1' );