Factorio is straightforward to archive because each world save is itself a ZIP file, but the surrounding mod environment still matters. A user can copy one .zip and preserve the map bytes, yet later discover that required mods or versions are missing. SaveEditor recommends backing up the saves directory together with mod/version notes and checking whether the installation is standard or portable before assuming %APPDATA% is authoritative. The page deliberately separates ZIP structural validity from the game-level compatibility of the serialized factory.
Which storefront context matters
Documented Factorio PC launchers/storefronts: Steam, GOG, standalone. The default Windows root is AppData/Roaming, but ZIP/portable installations can use a local game data directory according to Factorio configuration. The active storefront/account should be identified before any restore because cloud and local storage may not use the same path or container across editions.
Documented cloud behavior
Steam Cloud and GOG Galaxy cloud are documented. Cloud synchronization is useful for continuity, but it can also turn a restore into a conflict-resolution event. Let synchronization settle before making a manual backup, and keep an offline copy outside any folder monitored by the launcher or operating-system sync service.
Local save roots still matter
The researched local save boundary is Windows: %APPDATA%Factoriosaves; the known file or folder pattern is Save games are ZIP archives, normally named <save-name>.zip.. A cloud-enabled game still has concrete local data involved in ordinary play, and that local context is what you need when identifying which copy was modified most recently.
Avoid accidental overwrite loops
Copy the entire saves directory and, for important modded factories, also preserve the mods folder and mod-list/version context. Keep the original .zip extension and avoid unpack/repack cycles unless required by a known workflow. When restoring, close the game and launcher, preserve both the current local copy and the backup you want to test, then place the intended data in the matching profile/storefront location. Do not repeatedly open the game between different copies without noting which side the cloud client selected.
Compatibility and conflict checks
A save can load differently or fail when required mods/versions are absent. The fact that the file is a valid ZIP archive does not guarantee semantic compatibility with another Factorio environment. If progress disappears or rolls back, If a save is missing, verify whether the installation uses the standard user-data directory or a portable/custom write-data path. If loading fails, compare Factorio and mod versions. Resolve identity/path/cloud questions first. A cloud conflict is not proof that the save itself is corrupt, and a successful upload is not proof that files from another storefront are compatible.
Verification context: Reviewed against the current official Factorio Wiki application-directory documentation and PCGamingWiki save path.