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🧟 Project Zomboid · Server Settings

Project Zomboid Server Settings Explained

A Project Zomboid dedicated server reads two files: servertest.ini (the server box — name, ports, password, PvP, RCON, mods) and servertest_SandboxVars.lua (the world — zombie population and lore, loot rarity, XP, weather). Here's every setting that actually matters in plain English, with the gotchas that trip people up: the zombie population scale is inverted, loot rarity tiers differ between Build 41 and Build 42, and one anti-cheat toggle is openly buggy.

Keys & defaults checked against the current GamesOMG generator · last verified June 2026
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Don't want to hand-edit config files?
This page explains what each setting does. To actually build both files, the Project Zomboid config generator turns these into a ready-to-run servertest.ini + servertest_SandboxVars.lua — correct Lua tables, the right VERSION header, and a Build 41 / Build 42 toggle that follows the differences for you.
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Server Identity & Network

File: servertest.ini

Name, password, ports, and visibility — the file that controls the server box, not the game world.

SettingWhat it doesDefaultRecommended
PublicNameThe name shown in the in-game public server browser. Change it or you're one of a thousand identical "My PZ Server" entries.My PZ Serveryour name
PasswordRequired to join. Empty by default = open server. Set one to make it private (players still join via the browser or direct connect with the password).(empty)set one
DefaultPortUDP port players connect on. Forward it on your router and open it on the firewall.1626116261
UDPPortSecondary/direct-connect UDP port, one above the game port. Forward this one too.1626216262
MaxPlayersPlayer slot cap. Each player adds simulation load — set it to what your box can actually run, not the max you'd like.168–16
OpenOn by default — anyone with the password can join. Turn off to require accounts be whitelisted before they can connect.OnOn
PublicOff by default. Turn on to advertise the server in the in-game public browser; leave off for a friends-only server reached by direct connect.OffOff
PVPOn by default — players can damage each other. Turn off for a pure PvE/co-op server. (This is the master PvP switch; the safety dials are in PvP & Safety.)OnOff (co-op)
PauseEmptyOn by default — in-game time pauses when no one is online, so the world doesn't decay while nobody's playing.OnOn
Two UDP ports, not one: forward both DefaultPort (16261) and UDPPort (16262). RCON uses a third, separate TCP port. Open all the ones you actually use.
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RCON, Admin & Mods

File: servertest.ini

Remote console and the mod/Workshop load lists — the two lists must line up or mods silently fail.

SettingWhat it doesDefaultRecommended
RCONPortTCP port for the remote console most management tools and restart scripts use. Forward it separately from the game ports.2701527015
RCONPasswordEmpty by default. Set one before enabling any tool that connects over RCON — an empty password effectively means no remote access at all.(empty)set one
MapMap load order, semicolon-separated. Map mods usually want their map name added here, before the base map.Muldraugh, KYMuldraugh, KY
ModsMod load IDs (not Workshop file IDs), semicolon-separated. This list and WorkshopItems must line up for mods to actually load.(empty)
WorkshopItemsSteam Workshop file IDs to download, semicolon-separated. Each maps to one or more mod IDs in the Mods line.(empty)
Mods vs WorkshopItems: WorkshopItems is the file ID Steam downloads; Mods is the internal mod ID the game loads. They are different numbers and a mod needs both lines filled, or it downloads but never activates.
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PvP & Safety

File: servertest.ini

The PvP safety-toggle system and damage modifiers. PvP melee is heavily nerfed vs PvE by default.

SettingWhat it doesDefaultRecommended
SafetySystemPlayers individually toggle PvP on/off; you can only hurt someone if at least one of you is in PvP mode. On by default. Turn off for free-for-all while PvP is enabled.OnOn
PVPMeleeDamageModifierDamage multiplier for player-vs-player melee. Default 30 — PvP melee is deliberately reduced far below PvE so fights aren't one-hit.3030
PVPFirearmDamageModifierDamage multiplier for player-vs-player ranged attacks. Default 50.5050
The numbers are percentages, not raw multipliers: 30 means PvP melee lands at ~30% of its PvE damage. If players complain melee feels like pillow-fighting, that's why — raise it deliberately, don't assume it's a bug.
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Population & Zombies

File: servertest_SandboxVars.lua

How many zombies and how fast they move. Read the gotcha below before touching the population field.

SettingWhat it doesDefaultRecommended
ZombiesCoarse population step on an INVERTED legacy scale: 1 = Insane (most), 5 = None. Ships at 4. Modern PZ drives real population from the multiplier below — treat this as approximate.4 (Low)leave at 4
PopulationMultiplierFine multiplier on the overall population, 0–4. This is the real population dial in modern PZ — use it for everything between the coarse steps. Nests under ZombieConfig.1.00.6–1.0
DistributionWhere zombies cluster. 1 = Urban Focused (denser in towns); 2 = Uniform spreads them evenly across the map.1 (Urban)1
SpeedHow fast zombies move. 1 = Sprinters (the hard one), 2 = Fast Shamblers (default), 3 = Shamblers (classic slow), 4 = Random.2 (Fast Shamblers)3 (Shamblers)
The inverted-population trap: the top-level Zombies field counts down — 1 is the MOST zombies (Insane), 5 is None — and it's a legacy/back-compat value. To actually thin out or pack the horde, set PopulationMultiplier (0–4); leave Zombies at its default and tune the multiplier instead.
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Zombie Lore

File: servertest_SandboxVars.lua

The deep zombie ruleset — strength, infection, senses — nested under ZombieLore. This is where "how hard is it" lives.

SettingWhat it doesDefaultRecommended
StrengthHow hard zombies hit and how easily they pull you down. 1 = Superhuman, 2 = Normal, 3 = Weak.2 (Normal)2
ToughnessHow much punishment a zombie takes before it drops. 1 = Tough, 2 = Normal, 3 = Fragile.2 (Normal)2
CognitionHow smart zombies are. 3 = Basic Navigation (classic Romero shambler); 1 = Navigate + Use Doors makes them genuinely cunning.3 (Basic Navigation)3
TransmissionHow the Knox infection spreads. 1 = Blood + Saliva (default). "Everyone's Infected" makes every character turn on death regardless of bites.1 (Blood + Saliva)1
MortalityHow long after a bite until you die. Apocalypse default = 2–3 Days. "Never" effectively disables death-from-bite.5 (2–3 Days)5
ReanimateHow long after death a corpse rises as a zombie. Faster reanimation makes clearing bodies urgent.3 (0–1 Minutes)3
Sprinters vs shamblers lives in two places: Speed (in Population) sets the movement type, but Strength, Toughness, and Cognition here decide whether a horde is survivable. Dialing Speed to Shamblers while leaving everything else Normal is the most common "make it less brutal" tweak.
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Loot & XP

File: servertest_SandboxVars.lua

Loot scarcity and skill-gain rate. The rarity scale and its defaults DIFFER between builds — read the tip.

SettingWhat it doesDefaultRecommended
FoodLootHow much food spawns. Default Normal. The rarity scale here is shared by every loot category.4 (Normal)4
WeaponLootMelee and firearms. Default Rare — the classic dial for how combat-heavy a server feels.3 (Rare)3
AmmoLootBullets and shells. Default Normal. Pair a low value with common weapons for a "guns but no ammo" feel.4 (Normal)4
MedicalLootBandages, pills, disinfectant. Default Normal. Drop it for a server where injuries are dangerous to treat.4 (Normal)4
MechanicsLootCar parts and mechanic tools. Default Rare. Affects how easily players keep vehicles running.3 (Rare)3
XpMultiplierGlobal skill XP rate. 1.0 = vanilla. Bump to 2.0–5.0 for a faster-progression server.1.01.0–2.0
The scale changes between builds. Build 41 has a 5-tier rarity scale; Build 42 adds "Insanely rare" at the bottom for 6 tiers, so the same number can mean different things. Stock per-category defaults also vary by preset (e.g. weapons start Rare, ammo Normal). Set the build toggle in the generator first, then tune — and double-check defaults against a freshly-generated file.
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World & Time

File: servertest_SandboxVars.lua

Day length, climate, and the utility shut-off timers that turn a sleepy town into a survival crunch.

SettingWhat it doesDefaultRecommended
DayLengthReal-world time per in-game day. Default 3 = 1 Hour. Lower values make days fly by; longer ones suit slower, deliberate servers.3 (1 Hour)3
TemperatureOverall climate. Default 3 = Normal. Colder settings make winter survival much harder.3 (Normal)3
WaterShutWhen the mains water cuts out. B41 default 2 = 0–30 days (randomised). After this you're on rain collectors and stored water.2 (0–30 Days)2
ElecShutWhen the electrical grid cuts out. B41 default 2 = 0–30 days (randomised). After this you need generators.2 (0–30 Days)2
B42 expresses shut-off as a raw day count. In Build 41 Water/Power Shut-Off is a tier (0–30 days, 0–2 months…); in Build 42 it's a specific day number. The generator exposes a "shut-off day" field for the exact-day case — on B42, set that and treat the tier dropdown as approximate.
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Zombie Respawn

File: servertest_SandboxVars.lua

Whether and how fast cleared areas refill with zombies, nested under ZombieConfig. The single most-important long-server dial.

SettingWhat it doesDefaultRecommended
RespawnHoursIn-game hours before zombies respawn in a cell. Default 72. Set to 0 to disable respawning entirely — popular on long-haul servers where players want cleared towns to stay clear.720 (long server)
RespawnMultiplierFraction of the original population that respawns each cycle. Default 0.1 (10%). Lower it for a slow trickle back.0.10.1
RespawnUnseenHoursHow many hours an area must go unseen by players before zombies can respawn there. Default 16. Only matters when respawning is enabled.1616
RespawnHours 0 = no respawn. If your group clears a town and wants it to stay cleared, set RespawnHours to 0 rather than fighting the same horde forever. Leave it at 72 for an endlessly-dangerous world.
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Safehouses & Survival

File: servertest.ini

Player base claims and a couple of survival-rhythm switches. The whole safehouse system is off until you turn it on.

SettingWhat it doesDefaultRecommended
PlayerSafehouseLet players claim safehouses. Off by default — this is the master switch for the entire safehouse system.OffOn (group servers)
SafehouseAllowTrepassLet non-members enter a claimed safehouse uninvited. On by default — turn off to lock outsiders out entirely.OnOff
SafeHouseRemovalTimeReal-world hours of not visiting before a player is dropped from a safehouse. Default 144 (6 days).144144
HoursForLootRespawnIn-game hours before looted world containers refill. Default 0 = never (the usual long-server choice). Separate from sandbox loot rarity.00
SleepAllowedLet players sleep. Off by default on MP — sleeping fast-forwards time, which is awkward with others online.OffOff
KickFastPlayersAnti-speedhack that kicks players moving faster than should be possible. Off by default — the game's own docs warn it's buggy.OffOff (buggy)
Leave KickFastPlayers off. The official reference flags it as buggy — it can boot legitimate players (lag spikes, vehicles, mods read as "too fast"). It's a known footgun, not a recommended anti-cheat. HoursForLootRespawn at 0 also means containers never refill, which is what most persistent servers want.

Project Zomboid Server Settings FAQ

How do I change Project Zomboid server settings?
PZ reads two files for a world named servertest: servertest.ini (server box — name, ports, password, PvP, RCON, mods) and servertest_SandboxVars.lua (the world — zombie population, loot, XP, weather). Both live in your user folder under Zomboid/Server/ (managed hosts expose the same two files in their editor). Stop the server before editing — PZ reads them on boot and can overwrite changes made while it's running. Edit by hand or build both with the generator.
What's the difference between Build 41 and Build 42?
Build 41 is the long-stable build most multiplayer servers still run. Build 42 (MP released to the Unstable branch in late 2025) is the current direction — more sandbox settings and a reworked loot-rarity scale (B41 has 5 tiers; B42 adds "Insanely rare" for 6). The two files are ~95% identical; the differences are the loot options, a few build-only settings, and the VERSION header (4 for B41, 5 for B42). In the generator, set the build toggle to the build your server actually runs and the settings follow.
How do I make zombies fewer or slower?
Fewer: set PopulationMultiplier (0–4, in the SandboxVars file) below 1.0 — that's the real dial. Ignore the top-level Zombies field's number; it's an inverted legacy scale where 1 = the most zombies and 5 = none. Slower: set Speed to Shamblers (3). For an even gentler world, also drop Strength/Toughness toward Weak/Fragile and set Cognition to Basic Navigation. To stop cleared areas refilling, set RespawnHours to 0.
How do I tune loot and XP?
Loot rarity per category (Food, Weapon, Ammo, Medical, Mechanics…) uses a shared scale in servertest_SandboxVars.lua — but the tiers and stock defaults differ between Build 41 and Build 42, so set the build first. Lower numbers = scarcer. For skills, XpMultiplier sets the global rate (1.0 vanilla, bump to 2–5 for faster progression). Separately, HoursForLootRespawn in servertest.ini controls whether world containers refill over time — 0 means never.
What are sprinters vs shamblers?
That's the Speed setting in the SandboxVars file. Sprinters (1) run at full pace and are brutal — a few can overwhelm an unprepared player. Fast Shamblers (2) is the default — faster than a walk, slower than a run. Shamblers (3) are the classic Romero slow-walkers most co-op servers prefer. Random (4) mixes them. Speed sets the movement type; Strength, Toughness, and Cognition decide how dangerous each one is.
Why does my anti-cheat keep kicking legit players?
If you turned on KickFastPlayers, that's almost certainly it — the official reference openly flags it as buggy, and it can boot legitimate players during lag spikes, in vehicles, or with certain mods. Leave it off. For mod-mismatch kicks instead, the (blunt) lever is DoLuaChecksum in servertest.ini, though turning that off weakens file-integrity checking.