AI phrases in Reddit comments ("AI slop", "written by AI"), 2021 to 2026

Monthly counts of Reddit comments and threads in 100 large English-language subreddits with the phrase "AI slop" or an older phrase that calls something AI-made, such as "written by AI" or "sounds like ChatGPT", January 2021 to September 2026, 634,902,252 comments in all. Includes per-subreddit counts for 2021 and January to September 2026. Source: KissMyPost analysis of public Reddit posts and comments. This dataset accompanies the KissMyPost study How often Reddit comments call things "AI slop" or "written by AI". The method, charts and the full write-up are on that page. Files: ai-slop-reddit-monthly-2021-2026.csv: Monthly counts, January 2021 to September 2026. Comments, threads with comments, and comments and threads with "AI slop" or one of the older phrases, by month. October 2025 is flagged and left out of the article. ai-slop-reddit-subreddits-2021-2026.csv: Counts by subreddit, 2021 and 2026. All 100 subreddits in the sample: threads with comments and threads with a match, for 2021 and January to September 2026, with "AI slop" and the older phrases split for 2026. Method: Whole-word, case-insensitive phrase match in comment bodies; comments distinguished as moderator posts excluded; a thread counts once in each month it got comments. Measured: Share of threads with a comment saying "AI slop"; Share of threads with a comment using an older phrase such as "written by AI"; Comments containing "AI slop"; Comments containing the older phrases. All files contain aggregates only, no individual posts or user names.