AutoModerator is the most powerful tool Reddit gives moderators, but the official docs assume you already know YAML. Most new mods paste a random rule from r/AutoModerator, it works for a week, then something breaks and nobody knows why.
This guide walks through the full setup from a clean slate. No coding experience needed. Just a clear process.
What you actually want to do: configure AutoModerator without breaking your subreddit
You want AutoModerator to handle the boring repetitive work: removing spam, catching low-karma accounts, filtering link posts, and notifying the mod team. You don’t want to become a YAML expert, and you definitely don’t want to accidentally remove every post on your subreddit.
The good news: AutoModerator’s core logic is simple. The bad news: one wrong space or indentation can make a rule fail silently. So the real goal is to build rules you understand and can verify.
Before you start: what you need
- Moderator permissions: You need the “Manage Wiki Pages” permission. AutoModerator is just a wiki page controlled by the bot.
- A test subreddit (strongly recommended): Create a private subreddit (r/YourSubTest) and configure AutoModerator there first. You can break things freely without harming your main community.
- YAML basics: You don’t need to learn YAML fully, but you need to understand indentation. Two spaces matter. Tabs break rules.
- A throwaway or alt account: You’ll need a second account to test what AutoModerator actually does to regular users.
Step 1: Find the AutoModerator configuration page
Go to reddit.com/r/YOURSUBREDDIT/about/wiki/edit/automoderator. If you have wiki permissions, you’ll see a text editor. If you see a “wiki disabled” page, enable the wiki in your subreddit settings first.
This page is the “config” page. Everything AutoModerator does is controlled by the text you save there.
Step 2: Understand the basic rule structure
Every AutoModerator rule has three parts:
- What content it checks (type, author, title, body, domain)
- What conditions must be true (karma thresholds, account age, keywords)
- What action to take (remove, filter, report, approve)
Here’s the skeleton:
---
# This is a comment
type: submission
condition: ...
action: remove
action_reason: "Your reason here"
The --- separates rules. Without it, AutoModerator reads everything as one rule and gets confused.
Step 3: Write your first simple rule (removing spam links)
Let’s build a basic spam filter for link posts from domains you don’t trust.
---
# Block known spam domains
type: link submission
domain: [spam-site1.com, spam-site2.net]
action: remove
action_reason: "Known spam domain"
modmail: "Removed {{author}}'s link post to {{domain}}"
Save it, then go to the automoderator wiki page (not the edit page) to verify it saved correctly. The bot posts a confirmation comment when the config is valid.
Step 4: Add a removal reason and notification
A removal without a reason confuses users. Add comment to explain why the post was removed, and modmail to alert the mod team.
---
# Remove and notify
type: link submission
domain: [spam-site1.com]
action: remove
action_reason: "Spam domain"
comment: "Your post was removed because it uses a known spam domain."
modmail: "Spam link removed from {{subreddit}}: {{title}}"
The {{author}}, {{title}}, and {{domain}} variables pull info from the actual post. Use them so messages aren’t generic.
Step 5: Test with a throwaway or alt account
This is the step most people skip, and it’s the most important one.
- Post a link to
spam-site1.comfrom your alt account in your test subreddit. - Check if the post is removed.
- Check if the removal comment appeared.
- Check if modmail was sent.
- Post a normal link to confirm it still works.
If the rule works in the test subreddit, copy it to your main subreddit’s config page. If it doesn’t work, the issue is almost always indentation or missing --- separators.
Step 6: Schedule an automatic daily backup
AutoModerator configs can be wiped by a bad edit or a bug. Reddit keeps old versions in the wiki page history, but that’s not reliable enough for a serious subreddit.
Use a free automation tool to send a copy of your config to a private Discord channel or Google Drive daily. At minimum, manually copy the config text to a private document once a week. When a rule misbehaves, you’ll want a clean version to roll back to.
Common blockers and how to fix them
“AutoModerator didn’t remove the post”
The rule might have a syntax error. Check the wiki page for a comment from the bot saying “Invalid YAML.” Fix the indentation and save again.
“The rule removed too much”
Your condition is too broad. For example, checking body: "spam" will remove any comment containing the word “spam.” Use more specific regex patterns or combine conditions with and or or.
“The rule works, but I can’t see the removal reason”
Removal reasons are separate from AutoModerator. Create them in Mod Tools > Removal Reasons, then reference them with removal_reason: "reason_id" in your rule.
“The config saved but the bot says nothing”
The bot only comments when there’s a problem. Silence usually means valid config. Check by making a test post that should trigger a rule.
Practical example: building a “low account age” filter from scratch
Many subreddits want to stop brand-new accounts from posting. Here’s a real-world rule that filters posts from accounts younger than 14 days while notifying the mod team instead of auto-removing:
---
# Filter posts from accounts younger than 14 days
type: submission
author:
account_age: "< 14 days"
action: filter
action_reason: "Account too young ({{age}} days)"
modmail: "Post from account aged {{age}} days in /r/{{subreddit}}: {{title}}"
Using filter instead of remove sends the post to the mod queue for human review. That’s safer than auto-removing because some new accounts are legitimate users. You can manually approve them through the mod queue.
Test this in your test subreddit with a new alt account. If you don’t have one, create a fresh account and try posting immediately. It should land in the mod queue, not on the subreddit.
Action checklist for your first AutoModerator rule
- [ ] Create a private test subreddit
- [ ] Enable wiki pages in the test subreddit
- [ ] Open the AutoModerator config page
- [ ] Write one simple rule with clear separation (
---) - [ ] Save and verify the bot says the config is valid
- [ ] Test with an alt account from a different IP or browser
- [ ] Confirm the removal action and modmail
- [ ] Test a normal post that should NOT be removed
- [ ] Copy the rule to your main subreddit
- [ ] Set up a weekly backup of the config
Practical takeaway
AutoModerator is not a “set and forget” tool. Start with one rule, test it thoroughly, then add another. Use filter instead of remove when you’re unsure, check the mod queue daily, and always keep a backup of your config. A broken AutoModerator rule can silently kill your subreddit’s activity for days before anyone notices. If you’re dealing with a post that already disappeared before you had rules in place, the same logic applies: check what rule caught it before touching anything else.
For a broader comparison, review how to reddit automoderator before committing to one setup or workflow.
It also helps to compare this decision with Reddit post not showing when cost, trust signals, or setup quality matter.
FAQ
Q: What is the difference between remove and filter in AutoModerator?
A: remove deletes the post or comment from the subreddit immediately. filter removes it from public view but sends it to the mod queue for human review. Use filter when you want to avoid false positives.
Q: Does AutoModerator work on comments and posts at the same time?
A: Yes, but the rule must specify the type. Use type: submission for posts, type: comment for comments, and type: any if the rule should apply to both.
Q: Why does AutoModerator need the wiki page enabled?
A: AutoModerator is technically a wiki page controlled by the AutoModerator bot. The bot reads the wiki page and applies the rules. Without wiki access, the bot can’t read or update the config.
Q: Can AutoModerator send messages to users automatically?
A: Yes. Use the comment field to leave a public comment on the removed post, or modmail to send a private message to the moderators. For direct private messages to the user, use message_subject and message_body.
Q: How do I test an AutoModerator rule without affecting my real subreddit?
A: Create a private test subreddit, enable the wiki, and paste your rule there. Test with an alt account. Once you confirm it works, copy the rule to your main subreddit’s config page.
