I did read a very similar question to the question I'm asking now, but found it confusing, and it was more about when this site was in beta.

I just flagged a question that was, arguably, an exact duplicate of a stack overflow question.

For a question that is an exact duplicate, what are non-moderators expected to do? The site won't allow it to be given a close vote unless it duplicates a programmers question, which perhaps I should take as a hint.

Should such questions be flagged as possible merge candidates (though which direction the merge goes would presumably depend on the questions)? Should we just let a thousand flowers bloom? If such duplication is considered fine I don't want to waste moderator's time by flagging them.

2 Answers 2


There is no functional concept of a cross-site duplicate: questions can exist on two separate sites as long as they've been tailored to be on-topic for each site.

However, that rarely happens, and people cross-post the same question to multiple sites in misguided attempts to get their questions answered faster, or some questions that are off-topic for one site slip through the cracks and stay open.

So depending on the scenario, there are a few different things we can do:

Cross-posted questions

  • If it's cross-posted and on-topic here, link the Stack Overflow version in the comments and mention to the user they shouldn't cross post because Programmers is the right place for the question. I'd then flag the question on Stack Overflow so the moderators there can remove it.

  • If it's cross-posted and off-topic here, flag it for moderator review and mention it's a cross-post when you do so we can close it as off-topic before the community migrates it.

Non-crosspost duplicates

  • If the question is on-topic here, you can link Stack Overflow question in the comments and mention it's related. If you believe the Stack Overflow question belongs on Programmers and you have the reputation, vote to close it on Stack Overflow.

  • If the question is off-topic here, mention the Stack Overflow question in the comments and vote to close the question here as off-topic (not "off-topic; belongs on Stack Overflow").


In the case of identical questions, there's a network-wide policy: Is cross-posting a question on multiple Stack Exchange sites permitted if the question is on-topic for each site? The answer is no: posting the same question twice is not acceptable. This comes up now and then between Super User, Server Fault, Unix & Linux and Ask Ubuntu, which have overlapping scopes. We arrange to keep only one version open, ideally the single one that has answers already. In this case, please comment (so that potential answerers don't waste time repeating an answer that someone else wrote on another site), vote to close where you can, and flag for a speedy close.

If the questions are similar and posted by different users, it's a different matter. If the question is off-topic on one site, of course, close it as off-topic. If the issue is on-topic on both sites but the questions are suitably tailored to their respective sites, let both live: there's no notion of cross-site duplicates, and different communities might have different insights.

You must log in to answer this question.

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