Where the Reddit Comment Character Limit Comes From, and What Else Cuts a Reply Short

What is the Reddit comment character limit?

The number every answer repeats for the Reddit comment character limit is 10,000 characters, and the only Reddit source that states it is Reddit's own archived source code, not any page Reddit maintains today. The reddit-archive/reddit repository on GitHub validates the comment field with VMarkdownLength(['text', 'comment'], max_length=10000) in r2/controllers/api.py, so a comment longer than 10,000 characters fails before it is saved. Write replies to that ceiling, and treat the gaps in current documentation as a reason to test instead of assuming.

The repository is marked archived on GitHub and was last pushed on 17 October 2017, so it records how Reddit worked then. Reddit's live Data API reference describes the text field on POST /api/comment as "the raw markdown body of the comment or message" and gives no maximum. The Help Centre has no article on comment length either. Our Reddit post character limit page reaches the same conclusion from the other direction: titles and post bodies are documented, comments are not.

Where does the 10,000 character figure come from?

The figure comes from three places in Reddit's archived code, all set to the same number. Each one is a validator that rejects the text with the error message this is too long (max: %(max_length)s), defined in r2/lib/errors.py.

The edit path carries one detail worth knowing. In POST_editusertext, a self-post gets admin_override = c.user_is_admin, while a comment gets admin_override = False. Nobody, admins included, edits a comment past 10,000 characters in that code. A long reply that you later expand with an update hits the same wall as the original.

Does Reddit Premium raise the comment limit?

No documented change covers comments. Reddit's Help Centre changelog for 4 November 2025 lists Premium's higher content limits as "80,000 characters in post body (up from 40,000 for non-premium users)", a 30 minute video upload and 60 avatar outfit slots. Comments are not on the list. Plan every reply for the 10,000 character cap whether or not the account pays for Premium.

Can a subreddit set its own comment length limit?

Yes, and a community that sets one puts it far below 10,000. Reddit's full AutoModerator documentation gives moderators two checks for comments: body_longer_than, where "the comment's body must be longer than this number of characters to trigger the rule", and body_shorter_than, the mirror image. Both counts ignore "spacing and punctuation characters on either end", and an ignore_blockquotes directive drops quoted text from the count.

For comments, a rule that matches takes one of four actions: approve, remove, spam or report. A community that wants substantive answers writes a rule such as body_shorter_than: 50 with action: remove, and a one-line "Check out our tool" reply is gone before anyone reads it. The number stays invisible from outside, because AutoModerator's rules live on the subreddit's config/automoderator wiki page, which the moderators control.

A removed comment keeps looking normal to you, which is why nobody notices. Open the thread in a logged-out window: if your reply is missing there, a moderator or a rule took it down, and removed vs deleted on Reddit explains who acted and how to ask for it back.

What happens when a Reddit comment is too long?

A comment over the cap never posts, and one removed by a rule posts and then vanishes, so the symptom tells you which problem you have. Match what you saw to a row before you rewrite anything.

Splitting is the standard fix for a long answer. Post the first part, reply to your own comment with the second, and keep each under 10,000 characters. Reddit's archived code applies the cap per comment, not per thread.

How long should a reply to a Reddit thread be?

A reply to someone asking for help works at the length that answers their exact question, and that length sits nowhere near 10,000 characters. Put the answer in the first two lines and the detail below it, and say plainly if you built the product you mention, as the Reddit self-promotion rule asks.

Length also changes by platform, and a reply you draft once for three networks has to fit the tightest one. X documents 280 characters for a post without X Premium, as covered in X character limit, and Bluesky's lexicon sets 300 grapheme clusters, per Bluesky character limit. A Reddit comment has room for a worked answer. The two short-form networks hold a sentence and a link.

How does RedReplier handle comments and replies?

RedReplier watches posts and comments across every public subreddit for the keywords you track, alongside X, Bluesky, Facebook and Hacker News, and ranks each match by buyer intent. Matches land on your RedReplier dashboard within minutes of a post or comment going live, and Reddit alerts go out by email as digests on a cadence you set per keyword, from hourly to daily. RedReplier drafts a reply for each high-intent thread and never posts it for you: you review it, edit it to the subreddit's rules and length, and post it yourself from your own account.

That last step matters for length. A draft you post by hand is one you read first, so a reply that is too short for a community's body_shorter_than rule or too long for a thread that wants one line gets fixed before it goes out.

Frequently asked questions

How many characters can a Reddit comment have?

A Reddit comment holds 10,000 characters, the cap set in Reddit's archived source code for new comments. Reddit's current Data API reference and Help Centre give no number, so the archived code is the only Reddit source for the figure. Individual subreddits set lower limits of their own through AutoModerator.

Is the Reddit comment limit the same as the post limit?

No. A text post body holds 40,000 characters, or 80,000 on Reddit Premium, per Reddit's Help Centre changelog for 4 November 2025. A comment holds 10,000 characters in the archived source, and Premium's upgrade does not mention comments.

Does editing a comment reset the character limit?

No. Reddit's archived edit handler checks an edited comment against the same 10,000 character cap and sets no admin override for comments. Adding an update to a long reply fails once the total passes 10,000 characters.

Why did my Reddit comment disappear without an error?

A comment that posted and then vanished was removed, not rejected for length. A moderator, an AutoModerator rule such as body_shorter_than, or a spam filter took it down, and it still looks normal on your own screen. Check the thread logged out, then read the rules and message the moderators.

Do private messages on Reddit have a character limit?

Yes. Reddit's archived source validates a private message body at 10,000 characters, the same cap as a comment. Reddit's current documentation states no number for messages either.

How do I post a Reddit reply longer than 10,000 characters?

Split it. Post the first part as your comment, then reply to your own comment with the rest, keeping each piece under 10,000 characters. Put the direct answer in the first part, so the reply still works if nobody opens the second.

Where is Reddit's archived source code for the comment limit hosted?

The reddit-archive/reddit repository on GitHub carries the 10,000 character cap, archived and last pushed on 17 October 2017. The comment validator sits in r2/controllers/api.py, and the shared error message lives in r2/lib/errors.py. Nothing in that repository has changed since, so it shows a snapshot of Reddit's code at that date, not a live rule.

Does AutoModerator only remove comments that run too long?

AutoModerator checks length in both directions. body_shorter_than flags a comment for being too brief and body_longer_than flags one for running too long, and either match can trigger approve, remove, spam or report. The ignore_blockquotes directive strips quoted text before either check runs, so padding a short reply with a quote does not get past a minimum length rule.

How fast does RedReplier alert you to a new Reddit thread?

RedReplier puts a new match on your dashboard within minutes of the post or comment going live. Email alerts go out as digests on a cadence you set per keyword, from hourly to daily. The tool drafts a reply for each high intent thread it flags, but it never posts that draft for you. You read it, adjust it to the subreddit's length rules, and post it yourself from your own account.

Which other platforms does RedReplier track besides Reddit?

RedReplier watches posts and comments across every public subreddit alongside X, Bluesky, Facebook and Hacker News, ranking each match by buyer intent. A draft written for Reddit's 10,000 character comment room has to shrink to fit X's 280 character limit or Bluesky's 300 grapheme cluster cap. The same reply rarely fits all three networks unchanged.