How to Save in Icarus: Autosave, Save Files and Backups

If you are wondering how to save in Icarus, the short answer is that you don't have to: Icarus saves on its own. It autosaves on a timer, which has been every 10 minutes by default since the Week 196 update. It also saves on other triggers, exiting the game among them. There is no save button to hunt for. What you can control is how often the autosave runs, where the files end up, and how to roll back when something goes wrong.

This page covers all three, for solo play and for a dedicated server. It also covers the split that trips people up most: your character and your world are saved in two different places.

Checked against Icarus 3.0.29.157838-rel-DangerousHorizons

Week 251, released 24 September 2026. The autosave settings date from Week 196 (4 September 2025), and the backup system from Week 60 (27 January 2023).

How saving works in Icarus

RocketWerkz rebuilt autosaving in Week 196. Their own summary:

"You can now configure the timing between auto-saves, with the default frequency being upped from 1 minute to 10."

They added two cues so you can tell when a save has happened:

• A saving icon on the HUD appears while the save is being written. It shows for the host.
• The Escape menu shows the time since the last save, in minutes once it passes two minutes.

The timer is a safety net, not the only save. RocketWerkz's note: "there are other cases where a save can be triggered, such as exiting the game. So you don't need to worry about waiting around for 10 minutes to save automatically." Custom World Settings are also force-saved into the prospect file the moment you change them (Hotfix 2.3.22).

To play it safe, open the Escape menu before you quit. If the last save was a while ago, exit to the menu normally instead of killing the game from Task Manager or pulling the plug.

Changing the autosave interval

In single-player or a hosted co-op game, the setting is Settings → Gameplay → Save Game Frequency. The game's own description is "(Host only) Controls how many minutes between autosaves". It goes up to 60 minutes. A longer interval means fewer save stutters on a big base but more lost progress after a crash.

RocketWerkz say the dedicated server has the same option in its ServerSettings.ini, with "no limits on the dedicated server option". Their published template for that file hasn't been updated to include it, though, and we haven't tested the setting on our servers yet. If you want a different autosave interval on your GameServerKings server, contact support and we'll help you set it.

Only the host's interval matters in multiplayer. Clients don't save the world.

Where Icarus save files are

Icarus keeps three kinds of save data, and the first thing to know is that your character never lives on a server. Since the Week 53 decentralisation patch, RocketWerkz store all player data locally: "Now, all data will be saved locally, shifting data ownership to the players."

%LocalAppData% is C:\Users\<you>\AppData\Local. Paste it into the Explorer address bar to jump there.

The Icarus save file location on a dedicated server

The dedicated server only ever saves worlds. On a GSK server everything sits under /home/container, and the startup command passes no -UserDir flag, so the save folder is the default one inside the install:

/home/container/Icarus/Saved/PlayerData/DedicatedServer/Prospects/

Open it from the Files tab in your panel. Each .json in there is one world, and the name in LastProspectName in ServerSettings.ini is the one the server resumes at boot. The folder doesn't exist until the server has created or loaded its first prospect. If you are uploading a world to a brand-new server, create the Prospects folder yourself, as RocketWerkz's own migration guide says to.

Your players' characters are not in this folder, and no server-side action can reset, grant or restore them. Does Icarus Progress Save on a Dedicated Server? covers that split in full.

Backups, and rolling back a bad save

Icarus has kept rolling backups since Week 60: "Backups for Character data, Profile data and active Prospects are now created at 30-minute intervals and stored alongside the original file with a '.backup' extension." Up to 10 are kept, so roughly five hours of play.

The game tries to repair a save that was cut off mid-write when it next loads. If that fails, or you want to go back on purpose, restore by hand the way RocketWerkz describe it:

1. Close the game (or stop the server from the Console tab).
2. Copy the whole folder somewhere safe first. You are about to overwrite files.
3. Move the damaged file aside, for example MyWorld.json → MyWorld.json.old.
4. Take the newest .backup next to it and remove the .backup extension so it has the original name.
5. Start again and check the world.

RocketWerkz describe these backups for the game in general, not for dedicated servers specifically. On a server, check that .backup files actually sit next to your prospect before you rely on them, and keep taking panel backups from the Backups tab either way.

Never rename or edit a prospect .json

This is the one rule RocketWerkz shout about: "Changing the File Name, or the json data of your ProspectName.json, will corrupt your saved data. The corrupt data will save into the prospect and become UNRECOVERABLE." Restoring a .backup to the file's original name is fine. Giving a world a new name is not.

On a hosted server, the in-game backups are only half the story. The panel's Backups tab snapshots the whole server, prospects included. How to create a backup walks through it, and How to setup Schedules runs it on a timer. Take one before an Icarus update, a world move, or any time you are about to touch files by hand.

Moving a save between your PC and a server

A world moves as a single file:

1. On your PC, go to %LocalAppData%\Icarus\Saved\PlayerData\<SteamID64>\Prospects\ and find the world's .json.
2. Stop the server.
3. Upload the file, unrenamed, to Icarus/Saved/PlayerData/DedicatedServer/Prospects/. For large Open Worlds, SFTP is faster than the browser upload.
4. Start the server and load it by name (LoadProspect), or pick it from the lobby.

Going the other way works too: download the server's .json into your local Prospects folder. Since Week 147 the Load screen only lists prospects you actually have a save file for, so a world you played on someone else's machine won't appear until the file is on yours.

How to Set Up an Icarus Dedicated Server covers the first boot and LoadProspect, and Icarus Prospects on a Dedicated Server explains why a server holds one world at a time.

Common Questions

Is there a manual save button in Icarus?

Not as a separate command. The game autosaves on its interval and also saves on events such as exiting the game. The Escape menu shows how long ago the last save was. The dedicated server's admin commands (/AdminLogin, /KickPlayer, /BanPlayer, /UnbanPlayer, /ReturnToLobby, /ReturnToLobbyWhenEmpty, /AdminSay) include no save command either.

How often does Icarus autosave?

Every 10 minutes by default since September 2025. Before that it was every minute. Change it under Gameplay → Save Game Frequency (up to 60 minutes). On a dedicated server, contact support if you want a different interval.

Why did I lose progress after a crash?

Anything since the last autosave is gone. With the default interval that is up to 10 minutes. If the save file itself is damaged, restore the newest .backup as described above.

Does the server save my character?

No. Characters are stored on each player's PC. The server stores the world only.

Can I copy my friend's world to my server?

Yes, if they send you the prospect .json from their Prospects folder. Upload it unchanged. Only the player who created a world can resume it locally, which is exactly why moving it to a dedicated server is useful: after that, anyone can join it.

What to Read Next

• Does Icarus Progress Save on a Dedicated Server?: what your character keeps
• Icarus Prospects on a Dedicated Server: one world per server, and the lobby
• Icarus Server Settings Explained: the rest of ServerSettings.ini
• How to Play Icarus With Friends: hosting options compared

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