The guide
Subreddit rules, AutoMod and self-promotion
Every subreddit writes its own rules, and a second, invisible set lives in its AutoMod settings. Here is how both work and how to promote without getting removed or banned.
Where to find a subreddit's rules
Written rules sit in the subreddit sidebar on desktop and under "See community info" in the Reddit app. Many subreddits also keep a wiki with longer posting guidelines, and some pin a post explaining what is allowed. The checker above pulls the written rules for you and flags the ones about promotion.
What counts as self-promotion on Reddit
Anything that points readers to something you benefit from: your product, your blog, your newsletter, an affiliate or referral link. Reddit's old guideline, still quoted in many rule lists, is the 9:1 or 10% rule: no more than one in ten of your posts and comments should be about your own stuff. Some subreddits ban promotion outright, some allow it only in a weekly thread, and some welcome it if you disclose that it's yours.
What is Reddit AutoMod?
AutoModerator (AutoMod) is a bot every subreddit can configure. Mods write rules that automatically remove, filter, or flag posts and comments: from accounts younger than a set age, below a karma threshold, containing certain links or keywords, or matching a spam pattern. Those settings are private, so you can't read them the way you read the written rules.
When AutoMod removes a post you sometimes get a comment or message explaining why, and sometimes nothing at all. If posts vanish silently, the usual causes are account age, low karma, or a link the subreddit blocks. Check your account's age and karma with our Account Analyzer before you blame the rules.
How to promote in a strict subreddit
Answer questions instead of announcing things. In strict subreddits the only mention that survives is one that directly answers someone asking for a recommendation, written as help first and product second, with a clear note that it is yours. Use weekly promotion threads where they exist, and never post the same text in several subreddits.
What happens if you break the rules
The first step is usually a removed post. Repeat it and mods can ban you from the subreddit, and reports of spam can lead Reddit's admins to suspend or shadowban the account site-wide. That's why it pays to check the rules before posting, not after.