Best Project Zomboid Server Settings for Build 42
Build 42 reached the stable branch on 29 July 2026 with multiplayer, and it renamed or moved several server settings that Build 41 guides still quote. Here is where each setting lives on a 42.20 server, the values that decide how brutal the world is, and the ones that cost RAM and CPU on a busy Project Zomboid server.
A dedicated server named servertest reads its settings from ~/Zomboid/Server/ on Linux, or %USERPROFILE%\Zomboid\Server on Windows. servertest.ini holds the non-gameplay side: ports, passwords, PvP, player cap, mods and backups. servertest_SandboxVars.lua holds the world: zombies, loot, XP, utilities and respawn. Start the server with -servername and every file name changes with it.
If you are updating from Build 41, note three changes. Loot rarity is now a number per category instead of a 1-7 scale, XP is set in a MultiplierConfig block instead of XpMultiplier, and HoursForLootRespawn moved from the ini into SandboxVars. Servers that want to stay on B41 can use the legacy41 beta branch. New server? See how to make a Project Zomboid server.
What you'll need
A quick checklist before you begin — have these ready and the rest is easy.
- A dedicated server (Steam app 380870) on the default Build 42 branch, or legacy41 for B41.
- The config folder Zomboid/Server in the server user's home directory.
- Admin access for
reloadoptionsafter ini changes. - RAM to match
-Xmx: about 3 GB plus 500 MB per player.
Tune a Build 42 server, file by file
Set the player cap and server basics in servertest.ini
MaxPlayers defaults to 32 (range 1-100, admins excluded). The generated file warns that more than 32 players "will potentially result in poor map streaming and desync". PauseEmpty=true stops game time while nobody is online. SaveWorldEveryMinutes saves loaded parts of the map on a timer; at the default 0 the map is usually saved only when players leave an area.
PVP=true PauseEmpty=true MaxPlayers=32 SaveWorldEveryMinutes=0 DefaultPort=16261 UDPPort=16262
Pick the zombie population
In SandboxVars, Zombies is the preset: 1 Insane, 2 Very High, 3 High, 4 Normal (default), 5 Low, 6 None. Changing it also sets PopulationMultiplier in the ZombieConfig block. That multiplier ranges 0-4 and the presets map to Insane 2.5, Very High 1.6, High 1.2, Normal 0.65, Low 0.15. Build 41 guides quote Normal as 1.0, but on 42.20 the default is 0.65. The population also grows towards PopulationPeakMultiplier (1.5) by PopulationPeakDay (day 28).
Zombies = 4,
ZombieConfig = {
PopulationMultiplier = 0.65,
PopulationStartMultiplier = 1.0,
PopulationPeakMultiplier = 1.5,
PopulationPeakDay = 28,
},Decide whether zombies come back
On a fresh 42.20 server zombie respawn is off: RespawnHours defaults to 0, and 0 disables it (B41 defaulted to 72). To turn it on, set the hours before a cell may respawn, how long a chunk must be unseen (RespawnUnseenHours) and the fraction of the population that returns each time (RespawnMultiplier, 0-1). Keep ZombiesCountBeforeDelete at 300: the game warns that raising it, or setting 0, "may cause severe performance problems".
RespawnHours = 0.0, -- 0 = no zombie respawn RespawnUnseenHours = 0.0, RespawnMultiplier = 0.0, ZombiesCountBeforeDelete = 300,
Set loot abundance and loot respawn
Each loot category is now a number from 0 to 4. Lower means scarcer. Defaults: FoodLootNew 0.8, RangedWeaponLootNew 1.2, and 0.6 for weapons, canned food, medical and ammo. Loot respawn also lives here now. HoursForLootRespawn above 0 refills looted containers in towns after that many hours. MaxItemsForLootRespawn (5) skips fuller containers, and ConstructionPreventsLootRespawn protects buildings players have barricaded or built in.
FoodLootNew = 0.8, CannedFoodLootNew = 0.6, WeaponLootNew = 0.6, RangedWeaponLootNew = 1.2, AmmoLootNew = 0.6, MedicalLootNew = 0.6, HoursForLootRespawn = 0, MaxItemsForLootRespawn = 5, ConstructionPreventsLootRespawn = true,
Set the XP rate with MultiplierConfig
XpMultiplier is gone in Build 42. XP now lives in a MultiplierConfig block: Global (0-1000, default 1.0) sets the rate for every skill while GlobalToggle is true. Switch the toggle off to set skills such as Fitness or Strength one by one.
MultiplierConfig = {
Global = 1.0,
GlobalToggle = true,
},Memory, reloads and player counts
Size -Xmx for your players
The wiki suggests at least 3 GB for the server plus about 500 MB per player, more with mods. Set -Xmx in ProjectZomboid64.json on Linux or StartServer64.bat on Windows. The B42 bat ships at 16 GB, and the server fails to start if the machine has less.
The ini can reload live
The wiki says you can save servertest.ini while the server runs and apply it with the admin command reloadoptions. Its description covers the server options only, so restart after SandboxVars changes.
Start small on B42 multiplayer
When B42 multiplayer first shipped in unstable 42.13, the developers advised against more than 20 players on a server. The ini still warns that more than 32 can cause poor map streaming and desync.
Common problems & fixes
Hit a snag? These are the issues people run into most — and how to solve them.
A setting from a guide has no effect
The guide is probably written for Build 41. On 42.20, XpMultiplier became MultiplierConfig, loot rarity keys became FoodLootNew and similar, and HoursForLootRespawn moved into SandboxVars.
The server will not start after installing B42
The shipped StartServer64.bat asks for 16 GB. Lower -Xms and -Xmx to what the machine has.
Cleared areas never refill with zombies
RespawnHours is 0 by default on Build 42, which disables respawn. Raise it and set RespawnMultiplier above 0.
Desync and slow map loading with many players
The ini warns that more than 32 players can cause poor map streaming and desync. Lower MaxPlayers and keep ZombiesCountBeforeDelete at its default of 300.
Skip the setup — host it with ESAGAMES
Want these settings in a panel instead of two config files? Our Project Zomboid hosting lets you tune population, loot, XP and every sandbox setting from the panel, with Workshop mod support and automatic backups behind a protected Frankfurt network.
Frequently asked questions
Where are Project Zomboid server settings stored?
In Zomboid/Server in the home folder of the user running the server (Linux ~/Zomboid/Server, Windows %USERPROFILE%\Zomboid\Server). servertest.ini holds server options, servertest_SandboxVars.lua the gameplay rules, and the spawnregions and spawnpoints files the spawns.
What does Zombies = 4 mean in SandboxVars.lua?
It is the Normal zombie count preset. The scale runs 1 Insane, 2 Very High, 3 High, 4 Normal, 5 Low, 6 None, and changing it also sets PopulationMultiplier (Normal is 0.65 on Build 42).
Why don't zombies respawn on my Build 42 server?
Because RespawnHours defaults to 0 on 42.20, and 0 disables zombie respawn. Build 41 defaulted to 72. Set RespawnHours, RespawnUnseenHours and RespawnMultiplier in the ZombieConfig block to turn it on.
What replaced XpMultiplier in Build 42?
The MultiplierConfig block. Global (0-1000, default 1.0) applies to all skills while GlobalToggle is true; turn the toggle off to set each skill separately.
Where did HoursForLootRespawn go?
On Build 42 it is in servertest_SandboxVars.lua, not servertest.ini. Above 0, looted containers in towns and trailer parks refill after that many hours.
Can I still run a Build 41 server?
Yes. The developers kept Build 41 on the legacy41 beta branch; install it with app_update 380870 -beta legacy41 validate. B41 uses the older keys such as XpMultiplier and the 1-7 loot rarity scale.
Keep reading
Project Zomboid is a trademark of The Indie Stone. ESAGAMES is an independent hosting provider, not affiliated with or endorsed by The Indie Stone. You must own a legitimate copy of the game to play.