At least since four years and 15 months ago, a new rule was added all across the network known as Stack Exchange.

The rule:

Comments must be at least 15 characters in length.

This rule has been challenged many times, but always results in .

Some people have (had) figured out ways to break this long coveted rule.

The stats:

Stack Overflow has 4225 comments less than 15 characters in length.

Server Fault has 94

Meta Stack Exchange has 288

Super User has 193

TeX - LaTeX has 57

English Language & Usage has 40

I also checked a few other sites, which tended to have less than 30. But when you have 131 sites, they sure can add up quickly!

As you can see, by searching through those comments, 99% of them are useless, not constructive comments. Plus they knowingly or unknowingly broke the rule! So even if you find one that could be left alone, I still wouldn't mind it being deleted. Just like how questions from 4 years ago were on topic back then, but can now be closed for a close reason that just recently came out.


How should we proceed? Should we just leave it up to individual users to go through and flag these comments for a mod to review and delete? Should the team make comments that are less than 15 chars available for automatic deletion on one flag? Should the team just run their own query to delete all of these and be done with them? What do you think?

  • 3
    I would go with a daily process that delete such comments, that shouldn't exist in the first place. :) Sep 28, 2014 at 6:13
  • 4
    – jonsca
    Sep 28, 2014 at 7:07
  • 1
    I don't think coding a special flagging case for these comments is a useful solution. Then we'll just have a meaningless feature coded once all of them are gone. The last one that was posted on Stack Overflow is from 2011-07-01, so clearly they've since fixed the problem.
    – animuson StaffMod
    Sep 28, 2014 at 14:13
  • 3
    For some context: on SO, the last short comment in your query was posted over 3 years ago, 2011-07-01.
    – Arjan
    Sep 28, 2014 at 15:04
  • 2
    The 4k comments on SO should be < 0.1%, maybe around 0.01% scale of all comments on SO. I don't think we need to actively go on a search and destroy mission towards them. And as Arjan mentioned, it is not a recurring problem. If there is anything, we need more effort in cleaning up crap questions and answers.
    – nhahtdh
    Sep 28, 2014 at 18:46
  • @lostsock Those are different issues. They are 15 characters in length, they just exploit completely unrelated bugs to the hard-coded length requirement. Are you trying to identify every possible oddity that can occur in comments? Because your question only talks about the minimum character limit.
    – animuson StaffMod
    Sep 28, 2014 at 21:56
  • When I follow the links I can't find the comments. Has someone been on a deletion spree?
    – AndrewC
    Sep 29, 2014 at 1:08
  • 1
    @AndrewC I just checked the Stack Overflow query where it originally had over 4200 of these comments, but on Sept 28th, it appears they were taken care of, so now there is only 1 remaining on SO!
    Oct 25, 2014 at 0:45

3 Answers 3


Should we just leave it up to individual users to go through and flag these comments for a mod to review and delete?

That's an awful lot of flags to be fielded by moderators, most especially on SO. While it's a bit easier for mods to go through comment flags, it still takes effort away from a flag queue that's already pretty bloated. If the mod needs to check the context of the comment, it takes even longer. While most of those in the query are "thanks," "+1," and related, there are some that do link conversations together.

Should the team make comments that are less than 15 chars available for automatic deletion on one flag?

This approach would make things easier on moderators, but, as mentioned, doing comment removals in this fashion could also break the flow of conversation in your 1% of cases. In addition, as we all know, these types of "flagging drives" can lead to badge hunting, which may displace some of the discernment that should go along with flagging for removal. The upside would be that leaving things in the hands of the users will certainly going to get the job done eventually and does save having to make changes in the comment flagging rules.

As mentioned many times, comments are really second class citizens and can disappear at any time, but, even so, I think this is a lot of effort just for something that's really only partially based on cosmetic concerns and partially driven by righting the (minor) wrongs against "this long coveted rule."

  • Good answer. Yea, I think just to leave it up to the users to flag. On most sites, just 1 user can flag all the ones that are not constructive in like 1-3 days. SO would take about 40 days for just one user, but that site will likely have more people that go through and flag them too.
    Sep 29, 2014 at 3:19
  • @lostsock If it's done gradually, I would agree that it wouldn't be as much of a problem.
    – jonsca
    Sep 29, 2014 at 3:25
  • 1
    I agree with this answer; targeting only super-short comments is an irritating way to ignore the larger problem of useless comments. Just flag not constructive / too-chatty comments as you find them rather than targeting only a subset of them programmatically.
    – Laura
    Sep 30, 2014 at 15:41
  • @Laura Some people aren't as good at multi-tasking as others, and/or like to be as efficient as possible. I see nothing wrong in using queries as long as the user goes to the page, views the context, and flags accordingly. The whole purpose of many of the queues is not to just throw posts in the queues randomly. But to select ones based on user input and queries that target them for review.
    Oct 1, 2014 at 1:38

If you are going to flag a comment, it should be for a better reason than "it has fewer than 15 characters".

Consider a comment that says nothing but


and sits under the comment:

You may want to re-check the integration by parts on the second line: there appears to be a sign error there.

Deleting "Fixed" while keeping the first comment would be harmful. Neither an automatic process nor robo-flaggers enabled by one-flag-deletes policy can be trusted to deal with this exchange appropriately.


Most if not all the comments you found are not from people who broke the rule, with or without trying. Note the date on the comments: up to 2011-07-01. What changed on that day?

Starting on 2011-07-01, @ mentions in comments are stripped if they target the post owner. Since that day, @owner mentions are silently removed when the comment is posted.

I believe that on that day, the SE developers ran a one-time job to edit existing comments and remove @owner mentions. It's possible that the same code change made the length checks more accurate, I don't remember.

In any case, there's no point in hunting down old comments specifically because they're short. Most of them are useless, sure, but there are plenty of longer comments that are equally useless. Don't go on a flagging spree with this query. The priority should be on the comments that are harmful: rude or non-constructive comments, and comments that hide useful comments. The bulk of the comments that need deleting are obsolete or chatty comments that obscure relevant comments that add clarifications or provide criticism to a post. Focus on flagging the comments that cause other, useful comments to be hidden.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .