This is a moderation assistance tool that prevents vulgar words from being posted on a phpBB forum. When someone attempts to post on a forum, the post, subject and username (for guests) will be scanned for unallowed words. If a naughty word is detected, the post will not be entered into the database. Instead, the poster will be displayed an error message asking them to rephrase the post. The error message will include a preview of the post with the censor triggering words highlighted.

Private messages and basic user profile fields (like signature, location, messengers) are also checked when submitted.

The list of words that Censor Block will flag is controlled through the forum admin panel "Word Censors" area. An optional add-on to remove censor checks rendered obsolete by Censor Block is included.