How to Limit WordPress Post Revisions

Add define( 'WP_POST_REVISIONS', 5 ); to wp-config.php above the line "That's all, stop editing!", save, and WordPress keeps at most five revisions per post from then on. Constants below that line are read too late and ignored.

// wp-config.php, above "That's all, stop editing! Happy publishing."
define( 'WP_POST_REVISIONS', 5 );
define( 'AUTOSAVE_INTERVAL', 120 );   // optional: autosave every 2 minutes instead of 60 seconds

1. Copy wp-config.php to wp-config.php.bak in File Manager or over SFTP.
2. Add the line, making sure it is not duplicated elsewhere in the file.
3. Save, reload the site, and confirm it still loads.
4. Edit a post several times and check that its revision count stops at your number.

A white screen after saving usually means a missing semicolon or quote; restore the backup copy and try again. With WP-CLI, wp config set WP_POST_REVISIONS 5 --raw writes the same line safely.

A new limit trims a post only the next time it is saved, so clear the existing backlog separately, after a full database backup, using WP-CLI, a cleanup plugin or SQL. There is no undo for a database delete.

# WP-CLI: count, then delete all revisions
wp post list --post_type=revision --format=count
wp post delete $(wp post list --post_type=revision --format=ids) --force

# SQL in phpMyAdmin (check your table prefix first)
DELETE a, b, c
FROM wp_posts a
LEFT JOIN wp_term_relationships b ON (a.ID = b.object_id)
LEFT JOIN wp_postmeta c ON (a.ID = c.post_id)
WHERE a.post_type = 'revision';

If your prefix is not wp_, the SQL deletes nothing, which can look like success. In phpMyAdmin, use "Simulate query" first to see how many rows would be affected. On very large sites, delete in batches to avoid timeouts.

Plugins such as WP-Optimize or WP-Sweep do the same with a button and a schedule. The options table is often the next to bloat; see cleaning the wp_options table.

Watch two numbers: the revision count on a busy post, which should stop at your limit, and the database size in your hosting panel, which should grow much more slowly afterwards.

1. Edit a post several times and confirm the revisions list stops at your number.
2. Run wp post list --post_type=revision --format=count now and again in a month.
3. If the count keeps climbing, search wp-config.php for a second WP_POST_REVISIONS line or one placed below the stop-editing comment.
4. Repeat the cleanup after importing content from another site, since imports bring revision rows with them.

For overall database speed, the WordPress speed optimisation service includes database clean-up alongside caching and image work.