SyncCrate
Crusader Kings III guide · Updated
Same CK3 mods for every realm.
CK3 multiplayer needs every player on the same mods. SyncCrate copies the host's local mods, and saves if you want, to each friend, fixes mod paths that only work on one PC, and after the first time sends only what changed.
FreeOpen sourceNo cloudWin · macOS · Linux
// 01 Why
Why modded CK3 multiplayer won't start
Crusader Kings III compares a checksum of the game and its mods between players. Anyone with a different mod list, a different version of a mod, or one file changed by hand ends up with a mismatch, and the session either won't start or goes out of sync.
Workshop mods are the easy part: everyone subscribes. Local mods are harder, because each one is a folder plus a .mod file in Documents\Paradox Interactive\Crusader Kings III\mod, and that .mod file often points at a full path on the PC that made it.
SyncCrate copies the host's local mods to every PC, compares every file by content, and only the differences are copied. You see the list before anything changes.
// 02 What syncs
What SyncCrate syncs for Crusader Kings III
| Folder | Path in the game folder | Files |
|---|---|---|
| Mods | mod/Local mods: each mod's folder and its .mod descriptor. Descriptors for Steam Workshop mods (ugc_….mod) are skipped, because they point at Steam's folder. | All files |
| Save Files | save games/Campaign saves (.ck3). Optional; the host decides whether friends may sync them. | .ck3 |
// Where it looks
- Documents folder
Paradox Interactive/Crusader Kings IIIinside your Documents folder- macOS
~/Documents/Paradox Interactive/Crusader Kings III- Linux
~/.local/share/Paradox Interactive/Crusader Kings III- Anywhere else
- Point SyncCrate at the folder yourself, once
Built in for Crusader Kings III
- Turn mods on and off. Disabled mods move to a
_Disabledfolder the game doesn't load. - Game-running warning. SyncCrate warns you before syncing while Crusader Kings III is still open.
- Undo and history. Undo the last sync in one click, and put back any single file a sync replaced or deleted.
// 03 How it works
Sync Crusader Kings III in three steps
Install and add the game
Install SyncCrate on every PC and add Crusader Kings III in the Game Browser. Its folder is found automatically.
One PC hosts
The PC with the setup everyone should have clicks Start Hosting. The others pick it under Scan for Hosts on the same network, or paste its join code from anywhere.
Compare and sync
Check the list of new, changed and conflicting files, then Sync Now. Only the files that differ are copied, PC to PC.
TipEvery player needs the same game version and the same DLC. SyncCrate copies local mods and saves, not DLC or Workshop items.
// 04 Common problems
When Crusader Kings III mods don't match
The mod only works on the host's PC
The launcher often writes the mod's full folder path, like
C:/Users/<name>/Documents/…, into its.modfile. On a PC with another user name that path doesn't exist and the mod can't be found.The mod health check finds descriptors with a path that only exists on one PC and, on the host, makes them portable (
path="mod/<folder>") in one click. The old versions stay in File history.Checksum mismatch
One player with an older version of a mod, or a file they edited, is enough for a different checksum.
Everyone syncs the host's local mods before the session, so the files match byte for byte.
Mods copied but not in the playset
Which mods are on, and in what order, is saved in the launcher's playset, not in the
modfolder.SyncCrate copies the mods. On each PC, add them to a playset in the same order once, and the checksums match.
Taking over as host
If the usual host can't play, someone else needs the latest save to continue the campaign.
Allow the Save Files folder on the host, and the next host syncs the newest
.ck3save.
// 05 Crusader Kings III
Good to know
- Steam Workshop mods are kept by Steam in its own folder, outside the game's folder, so SyncCrate can't sync them. The Content page says how many you have, and friends subscribe to the same items.
- Real mod names. The Content page reads each mod's descriptor and shows its name and version instead of the file name.
- DLC isn't copied. Every player needs the DLC the mods and the campaign use.
- Your settings stay yours. Only the
modandsave gamesfolders sync.
// FAQ
Crusader Kings III questions
Do all players need the same mods in CK3 multiplayer?
Yes. The game compares checksums, and a different mod set or mod version causes a mismatch. Syncing the host's local mods, and subscribing to the same Workshop items, lines everyone up.
Where are CK3 local mods stored?
In Documents\Paradox Interactive\Crusader Kings III\mod on Windows and Mac, and ~/.local/share/Paradox Interactive/Crusader Kings III/mod on Linux. SyncCrate finds it automatically.
Does it sync Workshop mods?
No. Steam keeps them in its own folder. SyncCrate syncs local mods and skips the ugc_….mod descriptors the launcher creates for Workshop items.
Does it sync my playset?
No. Playsets are stored by the launcher, not in the mod folder. Set up the same playset on each PC once after syncing.
// Related game guides
All games · SyncCrate supports 100 games.
// Free · Open source · Windows, macOS, Linux
Same Crusader Kings III setup on every PC.
Install SyncCrate on each PC, one of you hosts, everyone else joins. No accounts, no cloud, nothing uploaded anywhere.