Top Moderation Keyword Filters & Blocklists for 2026

Content moderation, particularly in text form, poses significant challenges due to users' ability to circumvent filters through creative means such as leetspeak or indirect phrasing. Keyword filtering, a technique that scans for specific words or patterns, helps identify and manage harmful content across user-generated platforms like social media, chat rooms, and forums. However, this method has limitations, including evasion by users, lack of context understanding, and the need for constant updates to stay relevant with evolving language. Resources like premade keyword lists, public repositories, and research from trust and safety organizations help moderators quickly implement and maintain keyword filters. To enhance effectiveness, combining keyword filtering with large language models (LLMs) provides deeper insights into context and intent, balancing the need for fast automated responses with nuanced human judgment. Best practices in moderation include tailoring keyword lists to specific platform risks, localizing for language and culture, and integrating user reports and moderation reviews to refine systems over time.