How to back up Minecraft worlds and never lose them
Backups of worlds and servers: by hand, before every server start, and to Google Drive so a world survives reinstalling Windows.
A world with hundreds of hours in it can vanish because of a disk failure, a system reinstall or a bad mod. A backup takes a minute.
By hand
Worlds live in the build folder, in saves. Copy the world folder somewhere else — that's already a backup.
Google Drive
Connect Google Drive in the launcher: builds, worlds and servers go there with one button. On another PC, after signing in to the same profile, you can download them back. “Profile only” files are encrypted before upload.
Servers
In the server settings turn on a backup before every start and choose how many to keep. Scheduled backups are available too.
Before big changes
Updating the game version or adding a new mod? Back up first — then you can roll back any time.
Download TCLauncher — it's free.
FAQ
How do I move a world to another PC?
Upload it to Google Drive from the launcher and download it on the other PC after signing in to the same profile.
Can I open a world from a newer version in an older one?
No, that usually breaks the world. Only move worlds to newer versions and always back up.