Find the user-data folder rather than assuming the game installation contains your saved factory.
Start with the user-data directory
Factorio’s documentation distinguishes application files from user data and places saves in the saves subfolder of the latter. The documented standard locations are %appdata%\Factorio on Windows, ~/Library/Application Support/factorio on macOS and ~/.factorio on Linux. Installation methods and custom paths can change this. The documentation also notes a different prefix for Flatpak Steam installations, so consult it if the usual location is empty.
Make a copy you can identify
Our suggested manual process is to make a clearly named in-game save, finish saving and close the game. Find the corresponding recent file, then copy it to a separately named backup folder without moving or deleting the original. Include the date and game version in a small accompanying note. If you rely on mods, record those too, rather than assuming the save filename explains its requirements.
Do not turn a backup into an overwrite
Keep the copied archive intact. Before any restore, preserve the current save and consult the documentation for the installation you are using. A local duplicate on the same drive is useful for some mistakes but does not protect against loss of that drive. This guide concerns locating and copying saves; migrating blueprint storage and resolving Steam Cloud conflicts involve additional steps and should not be improvised by deleting files.
Go straight to the people who make it.
Factorio documentation: application and user-data directoriesSource check: 2026-09-29. General guidance; follow your device’s current instructions.