Lag and Desync on Valheim Servers

Fix lag, rubber-banding, and enemies that teleport on your Valheim server by working through the causes below, most likely first. If your server only uses part of its RAM, that is normal, and adding more will not fix the lag.

RAM Is Usually Not the Problem

A fresh Valheim world uses roughly 1.8 to 2.4 GB of RAM, and each area where players are active adds around 100 to 300 MB (Valheim Wiki: Dedicated servers). A server sitting at 2 GB of 8 GB is running as expected.

1. In the Game Control Panel sidebar, click Console
2. Look at the Memory graph below the console while the lag is happening

If memory is well below your plan limit, more RAM will not help. Work through the sections below. If memory is pinned at the limit, see Out of Memory (OOM) Crashes.

Quick Fix: Turn Crossplay Off for Steam-Only Groups

Most likely cause: Crossplay is on, but everyone in your group plays through Steam.

With Crossplay on, players do not connect to your server directly. Every player’s traffic goes through a PlayFab relay server, and the Valheim Wiki notes that players on a Crossplay server are more likely to see lag, timeouts, and disconnects because of that extra hop. Since 1.0, Steam-only servers with Crossplay on have also seen desync and rubber-banding.

1. In the Game Control Panel sidebar, click Server Options
2. Find the [REQUIRED] Enable Crossplay toggle
3. Turn it off. Server Options saves automatically and has no Save button
4. In the sidebar, click Console
5. Click Restart
6. Wait for the server to finish starting, then have everyone rejoin

With Crossplay off, the 6 digit invite code stops working. Players join by IP or through the community list instead.

If That Doesn’t Work

Lag Only Happens When You Play Together

Valheim does not simulate everything on the server. Each area of the world is handed to one player’s game, sometimes called the zone owner or chunk master, and that player’s PC runs the creatures and objects nearby (Valheim Wiki: Dedicated servers).

If that player has a slow PC, a lot running in the background, or a poor connection, everyone nearby sees the effects. Common signs are enemies teleporting, hits landing late, and chests or doors responding slowly.

1. Note which player was first into the area where the lag happens
2. Ask that player to leave the area and come back. Another player takes over the area
3. If the lag stops, let the player with the strongest PC and best connection enter busy areas first

Lag Spikes on a Regular Interval

If the lag hits at the same interval, it is usually the world save. Each save briefly pauses the server, and the pause gets longer as the world grows.

The [REQUIRED] Backup Interval field on the Server Options page sets how often the world saves, despite its name. It maps to -saveinterval and defaults to 1800 seconds (30 minutes). See Backup Interval.

1. In the Game Control Panel sidebar, click Server Options
2. Find the [REQUIRED] Backup Interval field
3. If it is set lower than 1800, raise it back to 1800
4. Click outside the field to save it
5. Restart the server

A longer interval means fewer spikes, but more progress lost if the server stops uncleanly. Avoid splitting the group across many distant areas at once, since every loaded area adds to the save.

Old Worlds and Large Bases

Valheim worlds get heavier with age. Every explored area, tamed animal, item on the ground, building piece, and terrain change is tracked by the server and written on every save.

Lag that shows up near big bases, animal pens, or heavily terraformed areas, and not out in the wilds, points here. Clear dropped items, reduce large animal pens, and spread big builds across fewer loaded areas.

Mods (BepInEx)

A single badly optimized mod can cause lag no matter how much RAM the server has. Test by taking recently added mods out, one at a time.

1. Make a backup of your world first. See Backing Up Your Valheim Server
2. In the Game Control Panel sidebar, click File Manager
3. Open the BepInEx/plugins folder
4. Move the most recently added plugin out of plugins into another folder, using Rename/Move from the … menu next to it
5. Restart the server and test
6. If the lag is gone, that mod is the cause. If not, move it back and try the next one

If the plugin is also installed on players’ games, remove it there too while you test. Crossplay and BepInEx mods cannot be used together, so a modded server should already have Crossplay off.

Check the Network Path with MTR

If none of the above explains it, the problem may be on the route between a player and the server. Lag that affects only one player usually points here.

1. Have the affected player press F2 in game and note the ping value
2. Have them run an MTR test to your server’s IP for at least 100 sends or 5 minutes
3. Save the report for support

Sustained packet loss at the final hop, your server, is the result that matters. Loss at a middle hop that clears by the final hop is usually not the cause.

Still Not Working?

If none of the above solutions resolve your issue, contact our support team with:

• Your Server UUID
• When the lag happens (all the time, at intervals, only in certain areas, or only for certain players) and whether Crossplay is on or off
• An MTR report from an affected player and a list of any installed mods