How can I clear the channel history in Slack?

Question

How can I clear the channel history?

The channel in question is a private channel created by me and is not (yet) archived.

Answer 1

It's possible to batch delete messages through the Slack archives page, but this only lets you delete one page of messages at a time and does not delete any corresponding file uploads.

A better solution that deletes all messages from channels and/or groups, including file attachments, is this Python library: slack-cleaner2 (this replaces the deprecated slack-cleaner). You'll need to be familiar with the programming language Python to use it.

Answer 2

A very fast way to do this is to recreate the channel:

1. Open your channel in Slack
2. Click the config button and choose "Additional Options"
3. Choose "Rename the Channel" and name it something (like "old-channel")
4. Create a new channel with the same name as the original

In my case, I archived the old channel afterwards.

Answer 3

Now, we can set a private channel or direct message retention policy on Slack.

For example, if you set a retention policy of one day, all messages in the channel or direct message will be deleted after one day.

FYI: Set-private-channel-and-direct-message-retention-policies