Changing your Mastodon joined date with PostgreSQL
Recently, I moved my Mastodon server to a new instance. While the original creation date of the previous one was very special to me, I searched for a way to permanently change the date I joined Mastodon to match this special date.
After finding the relevant fields in the PostgreSQL database it turned out to be quite easy: Assuming you have root access to your self-hosted Mastodon instance, the process is pretty straightforward and the following commands will lead to success:
Log into the „mastodon“ account (following the best-practices install, its name should be exactly this) with
su mastodon
Then enter the specific database with the „psql“-command:
psql -d mastodon_production
Once you’re there, simply follow the example below to change the „joined“ date of your Mastodon-account. Change the date and the corresponding user, then press „Enter“.
UPDATE accounts SET created_at='2025-05-12 19:18:00' WHERE username='oliver‘;and finish the process with
exit
That’s it - the change is immediate so there is no need to restart PostgreSQL or the corresponding Mastodon-services!
