--- title: "Factorio Server Saves and Autosaves" description: "How Factorio saves and autosaves work on a server, where they live, and how to restore one without losing the world." url: "https://www.gameserverkings.com/knowledge-base/factorio/factorio-server-saves-and-autosaves/" category: "Factorio" category_url: "https://www.gameserverkings.com/knowledge-base/factorio/" published: "2026-09-12T06:30:47.025Z" updated: "2026-09-12T06:32:35.847Z" source_format: "markdown" site: "GameServerKings" --- # Factorio Server Saves and Autosaves A Factorio server runs exactly one save file, and that file is the only thing that matters if anything goes wrong. Autosaves rotate on a fixed cycle and overwrite each other, so they are a rollback mechanism rather than a backup. This page covers where the save lives on your server, how the autosave cycle actually works, how to bring your own world across, and what a real backup looks like. > [!NOTE] The short version > Your world is the `.zip` at the root of your file tree, named by the **Save Name** field — `gamesave.zip` by default. Autosaves cycle through 5 slots and will eventually overwrite themselves. Before anything risky, download a copy to your own machine. That is the backup. ## Where the Save Lives Read it straight off the startup line your [Factorio server](/games/factorio-server-hosting/) runs: ```text ./bin/x64/factorio --port --server-settings data/server-settings.json --start-server gamesave.zip ``` `--start-server` is followed by the save path, and on your server that path is `gamesave.zip` at the **root** of the file tree — beside `bin/`, `data/` and `mods/`. It is not inside a `saves/` folder, which is where Factorio puts saves on a desktop install and where most guides will tell you to look. The name comes from the **Save Name** field on the **Startup** tab. Change that field to `bigfactory` and the server will look for `bigfactory.zip`. Note the field takes the name **without** the `.zip` extension — the startup line appends it. ## Why the Save Must Exist Before the Server Starts The headless build cannot generate a world at boot. The official wiki is explicit: **"You will need to create your save file before you start the server, as the dedicated server REQUIRES a save file to be provided."** Your installation handles this, running the documented `--create` step against your **Save Name** value. The consequence to remember is what happens if you point **Save Name** at a file that does not exist: the server will not start, and the console will say it cannot find or open the zip. That is the correct error, not a fault — check the filename in the **File Manager**, including case and the missing `.zip`. ## The Autosave Cycle Two settings drive it, and Wube documents both in the shipped `server-settings.example.json`: | Setting | Value on your server | Wube's comment | |---|---|---| | `autosave_interval` | **Auto Save Interval** field, default 10 | **"Autosave interval in minutes"** | | `autosave_slots` | Fixed at 5, not shown in the panel | **"server autosave slots, it is cycled through when the server autosaves"** | "Cycled through" is the important phrase. With 5 slots and a 10-minute interval you hold roughly 50 minutes of history. The sixth autosave overwrites the first. If a mistake goes unnoticed for an hour — a misfired deconstruction planner, a train rerouted into a smelter column — the autosaves have already rotated past it. Two more behaviours are worth knowing: - The headless server **"Saves the game on exit (and autosaves normally)"**, per the wiki. A clean shutdown through the panel writes the world out; the stop command is `/quit`, which is the graceful path. - The game **"is paused while there are no players connected"** unless you disable `auto_pause`. A paused server does not autosave, because no ticks are passing. An empty server is not quietly churning through its autosave slots. > [!TIP] Save on demand before anything risky > `/server-save` from the panel **Console** writes the world immediately. Run it before installing a mod, before a version change, and before letting a new player loose with a nuke. It costs a few seconds and it does not consume an autosave slot. ## Autosave Options in `server-settings.json` Two keys change how saving behaves, and neither is exposed as a Startup field — edit them in `data/server-settings.json`: `autosave_only_on_server` (default `true`) — Wube: **"Whether autosaves should be saved only on server or also on all connected clients. Default is true."** Left on, your players' machines are not writing copies of your world. Turning it off gives every connected client a local copy, which is an accidental distributed backup and also a way to annoy everyone with periodic stutter. `non_blocking_saving` (default `false`) — the one setting in the file Wube warns about in its own comment: **"Highly experimental feature, enable only at your own risk of losing your saves. On UNIX systems, server will fork itself to create an autosave."** On a large factory it removes the freeze every player feels when the server saves. The trade is stated plainly in that quote. `autosave_interval` and `autosave_slots` are both managed by the panel, so changing them in the file does nothing that survives a restart. Use the **Auto Save Interval** field. ## Uploading a World From Your Own Game Bringing across a single-player save, or a world your group started on someone's PC, takes four steps. 1. **Find the save on your machine.** The official wiki gives the user data directory per platform: `%appdata%\Factorio` on Windows, `~/Library/Application Support/factorio` on macOS, `~/.factorio` on Linux. Saves are in the `saves` subfolder as `.zip` files. 2. **Check the version.** The wiki's compatibility ladder caps each build at saves **"up to"** its own version — `2.0.x` **"loads saves from 1.0.0 up to 2.0.x"** — so a world from a newer build will not open on an older server. Match the server to the save, not the other way round. 3. **Stop the server, then upload the zip to the root of the file tree** through the **File Manager**. 4. **Set Save Name to the filename without `.zip`** and start the server. Watch for `Hosting game at` in the console. > [!IMPORTANT] Mods travel with the world, not inside it > A modded save will not load unless the same mods are present in `mods/` on the server. Upload the zips too — see [how to install Factorio mods](/knowledge-base/factorio/how-to-install-mods/), which covers why the server will not fetch dependencies on its own. ## What a Real Backup Looks Like Autosaves protect you from the last hour. They do not protect you from a corrupted file, a bad mod removal, or someone with admin rights and bad judgement — all of those get autosaved straight over the top. The official wiki's own advice, in the context of upgrading: **"It is recommended to create backups from this directory (of saves, config, etc) before installing a new version."** A workable routine: - Run `/server-save`, then **download** the zip to your own machine. Off-server is what makes it a backup. - Do this before every version change, every mod change, and on a schedule that matches how much progress you would accept losing. - Keep the old copy. A save is a few megabytes; a 200-hour factory is not replaceable. ## Common Questions ### Where are the autosave files? In the server's `saves` folder, written by the game itself rather than by the startup line. Open the **File Manager** and look there — the rotation means the names cycle, so sort by modified time to find the newest. ### How do I roll back to an autosave? Stop the server, copy the autosave you want to the root of the file tree, rename it to match your **Save Name**, and start. Keep the file you are replacing. ### Can I run more than one world on the same server? One at a time. Upload both zips, and switch by changing **Save Name** and restarting. The inactive world is untouched. ### Does changing Save Name create a new world? No. It changes which existing file the server loads. If no such file exists the server will not start. ### Why is my server freezing every few minutes? That is the autosave on a large map. Lengthen **Auto Save Interval**, or read Wube's warning on `non_blocking_saving` above and decide whether the trade is one you want. ### Do autosaves survive a reinstall? Assume not. A reinstall rewrites the server files. Download anything you care about first. ## What to Read Next - [How to Set Up a Factorio Dedicated Server](/knowledge-base/factorio/factorio-dedicated-server-setup/) — first boot and the file tree - [Factorio server-settings.json: Every Setting Explained](/knowledge-base/factorio/factorio-server-settings-json/) — the saving keys in context - [How to Install Factorio Mods on a Dedicated Server](/knowledge-base/factorio/how-to-install-mods/) — why a modded save needs its mods uploaded too --- Made with 💜 by GameServerKings