- Where Settings Live
- Server INI Settings
- Players and Access
- PVP and Safety
- Sleep
- Voice Chat and Safehouses
- Sandbox Settings - Zombies
- Population
- Speed, Strength, and Toughness
- Infection and Respawn
- Sandbox Settings - Loot and Progression
- Loot Rarity
- Progression
- Build 42 New Settings
- Animals and Livestock
- Crafting, Basements, and Darkness
- Build 42 Game Modes
- Quick Presets by Group Type
- Getting Started
Project Zomboid has one of the deepest server configuration systems of any survival game. Two separate config files, dozens of settings in each, and Build 42 added more on top. If you have ever opened your server files and wondered what half the options actually do, this guide breaks down the ones that matter.
We will cover the server INI (networking and admin), sandbox settings (zombies, loot, progression), and Build 42 additions like animals, crafting, and the refreshed game modes. If you are still setting up your server, start with our Build 42 setup guide first, then come back here.
Where Settings Live
Project Zomboid splits configuration into two files:
| File | Path | Controls |
|---|---|---|
| [servername].ini | Zomboid/Server/[servername].ini | Server-level: players, PVP, passwords, networking, safehouses |
| SandboxVars.lua | Zomboid/Server/[servername]_SandboxVars.lua | Gameplay: zombies, loot, XP, weather, world rules |
The file names include your server name - if you named it “MyServer” instead of the default, look for MyServer.ini and MyServer_SandboxVars.lua.
How to edit them: On WinterNode, use the File Manager or SFTP to navigate to Zomboid/Server/ and open the files directly. Some settings (server name, admin credentials, beta branch) are also available through the panel’s Server Options tab without needing to edit files. For everything else, stop the server before editing, make your changes, then start it back up.
Warning
If you use the in-game /changeoption command to modify settings, those changes revert on restart unless you also edit the actual file. For permanent changes, always edit the config file directly.
Server INI Settings
These control how your server behaves at the network and administration level. Most are set-and-forget.
Players and Access
| Setting | Default | What it does |
|---|---|---|
| MaxPlayers | 16 | Maximum concurrent players. Admins bypass this limit. |
| Open | true | If false, only whitelisted players can join. |
| Public | false | If true, your server appears in the in-game browser. |
| Password | 12345 | Server password. Change this immediately. |
For private groups, leave Public=false and share the IP directly. See our connecting guide for how players join by IP, and the quick start guide for setting up a whitelist and server admins.
PVP and Safety
| Setting | Default | What it does |
|---|---|---|
| PVP | true | Enables player-vs-player damage. |
| SafetySystem | true | Lets players toggle PVP on/off individually (skull icon). |
The Safety System is PZ’s PVP opt-in. Players can individually toggle PVP mode, with a skull icon marking those who are flagged. Good middle ground for servers that want PVP available without it being a constant threat. For pure PVE, set PVP=false. For full PVP, set PVP=true and SafetySystem=false.
Sleep
| Setting | Default | What it does |
|---|---|---|
| SleepAllowed | false | Whether players can sleep at all. |
| SleepNeeded | false | Whether players get tired and need sleep. |
Sleep in multiplayer requires all online players to be in bed simultaneously before time advances. Works for 2-3 friends. On anything larger, one player staying awake blocks everyone. Most servers leave both at false.
Voice Chat and Safehouses
PZ has built-in proximity voice chat (VoiceEnable=true by default). Most groups use Discord instead, but proximity chat works well for roleplay servers. Key settings: VoiceMinDistance (10 tiles), VoiceMaxDistance (300 tiles), and Voice3D (directional audio).
Safehouses (PlayerSafehouse=false by default) let players claim and protect buildings. Useful for PVP servers. Set SafehouseDaySurvivedToClaim to 3-7 days to prevent new players from instantly locking down the best buildings.
Sandbox Settings - Zombies
This is where PZ’s real depth lives.
Population
| Setting | Default | What it does |
|---|---|---|
| Zombies | Varies by mode | Overall density: Insane, High, Normal, Low, or None. |
| Distribution | Urban Focused | Urban Focused puts more in cities. Uniform spreads evenly. |
| PopulationStartMultiplier | 1.0 | Population level on day 1. |
| PopulationPeakMultiplier | 1.5 | Population at peak day. |
| PopulationPeakDay | 28 | In-game day when population hits its peak. |
The population ramps up over time. Default settings start at normal density and climb to 1.5x by day 28. If you want consistent density from day one, set Start and Peak multipliers to the same value.
Speed, Strength, and Toughness
| Setting | Values | Notes |
|---|---|---|
| Speed | Sprinters, Fast Shamblers, Shamblers, Random | Shamblers is classic PZ. Sprinters change the game entirely. |
| Strength | Superhuman, Normal, Weak, Random | Affects grab/attack damage. |
| Toughness | Tough, Normal, Fragile, Random | How many hits to kill. |
| Cognition | Navigate + Use Doors, Navigate, Basic, Random | Higher cognition = zombies open doors and path around obstacles. |
| Memory | Long, Normal, Short, None | How long zombies remember your last position. |
The most common adjustment is Speed. Fast Shamblers add urgency without the instant-death feel of Sprinters. Random rolls per zombie, so you will occasionally meet a sprinter in a crowd of shamblers.
Tip
If you want Sprinters but the difficulty feels overwhelming, pair them with Fragile toughness and Weak strength. Fast but easy to kill creates a different kind of tension than tough shamblers.
Infection and Respawn
| Setting | Default | What it does |
|---|---|---|
| Transmission | Blood + Saliva | How Knox Infection spreads. Options: Blood + Saliva, Everyone’s Infected, None. |
| RespawnHours | 72 | In-game hours before zombies respawn in cleared areas. 0 = no respawn. |
| RespawnUnseenHours | 16 | Hours a chunk must be unseen before zombies can respawn. |
| RespawnMultiplier | 0.1 | Percentage of peak population that respawns each cycle. |
Zombie respawn is heavily debated. With respawn enabled, clearing an area is temporary. Apocalypse mode in Build 42 now disables respawn by default, making cleared areas stay cleared. For permanent progress, set RespawnHours=0.
Sandbox Settings - Loot and Progression
Loot Rarity
| Setting | Values |
|---|---|
| FoodLoot | Extremely Rare to Abundant |
| WeaponLoot | Extremely Rare to Abundant |
| OtherLoot | Extremely Rare to Abundant |
These control initial loot density in containers. Apocalypse mode in Build 42 has been rebalanced with more plentiful firearms to reflect a 1993 Kentucky setting.
Loot respawn is controlled in the INI file (HoursForLootRespawn), not sandbox settings. Default is 0 (no respawn). ConstructionPreventsLootRespawn=true stops loot from respawning in buildings where players have built structures.
Progression
| Setting | Default | What it does |
|---|---|---|
| XpMultiplier | 1.0 | Scales all XP gain. 2.0 = double XP. |
| Farming | Normal | Crop growth speed. Very Fast to Very Slow. |
For multiplayer servers, bumping XpMultiplier to 1.5-2.0 is common. Respects players’ time without trivializing progression. Farming speed matters more in Build 42 since crops now have health and need active maintenance.
Build 42 New Settings
Animals and Livestock
Build 42 adds domestic animals (cows, pigs, chickens, sheep) and wild animals (deer, rabbits). Key sandbox settings:
| Setting | Default | What it does |
|---|---|---|
| Aging Modifier Speed | Normal | How fast animals grow. Normal is roughly 200 in-game days from calf to cow. |
| Milk Increase Speed | Normal | Rate of milk production. |
| Wool Increase Speed | Normal | Rate of wool production. |
For servers with shorter expected lifespans, speeding up the aging modifier lets your group benefit from animal husbandry before interest fades.
Crafting, Basements, and Darkness
Crafting: Build 42 overhauled crafting with new disciplines (blacksmithing, pottery, stone working, brewing). Multi-stage crafting means the XpMultiplier has a compounding effect on how fast players reach advanced tiers.
Basements: Houses can now spawn with hidden basements and bunkers, controlled by a sandbox frequency option. They are intentionally uncommon by default.
Darkness: Build 42 made nights significantly darker. The Darkness During Night setting ranges from Pitch Black to Bright. If your group finds nights unplayable, bump it up before installing mods.
Build 42 Game Modes
Build 42.15 refreshed the game mode system. Each mode is a sandbox preset you can use as-is or as a starting point.
- Apocalypse - The “lore canon” mode. Zombie respawn disabled. Firearms more plentiful. Tuned for authentic 1993 Kentucky. The intended experience.
- Outbreak - For players with limited time. Faster skill progression, more forgiving farming/animal timelines, adjusted loot density. Still challenging if you overextend.
- Extinction - Veterans only. Sprinters as default zombie speed. Scarce supplies, harder hits. Not recommended for first-time players.
- Rising - The “cozy apocalypse.” More building materials, less combat pressure. Designed for homesteading and base-building.
Info
Start with any game mode preset and customize from there. Select the mode closest to what you want, then tweak individual settings that don’t fit your group.
Quick Presets by Group Type
Casual / New Players: Start with Rising or Outbreak. Shamblers, Normal or Low population, XP at 1.5-2.0, PVP off.
Hardcore Survival: Apocalypse preset. Fast Shamblers or Sprinters, Normal population, XP at 1.0, Rare loot, respawn disabled.
PVP Server: PVP on, SafetySystem off, Safehouses enabled with 3-day claim timer, AnnounceDeath on, XP at 2.0 to offset frequent deaths.
Roleplay: Proximity voice on, GlobalChat off, ShowFirstAndLastName on, DisplayUserName off, Safehouses enabled, Shamblers.
Getting Started
WinterNode gives you full access to both config files through the File Manager and SFTP. Edit servertest.ini and SandboxVars.lua, restart, and your changes take effect. No command line, no SSH.
All Project Zomboid servers run at $1.99/GB with no CPU limits and unmetered storage. Build 42 servers need at least 8GB - see our setup guide for sizing recommendations.
Frequently Asked Questions
Yes. Admins can use the /changeoption command in-game or edit the SandboxVars.lua file directly. However, changes made in-game revert after a restart unless you also update the file. For permanent changes, edit the config file and restart the server.
servertest.ini controls server-level settings like max players, PVP, passwords, and networking. SandboxVars.lua controls gameplay settings like zombie behavior, loot rarity, XP rates, and world rules. Both files live in the Zomboid/Server/ directory.
For most multiplayer servers, yes. Sleep requires all online players to be in bed at the same time to advance time. This works for small groups of 2-3 friends, but anything larger and one player being awake blocks everyone else.
Build 42.15 introduced four refreshed modes: Apocalypse (lore canon, realistic survival), Outbreak (faster-paced, less downtime), Extinction (veteran difficulty with sprinters), and Rising (relaxed base-building focus). Each mode has a matching Custom Sandbox preset you can tweak.
Edit the Speed setting in SandboxVars.lua. Set it to 1 for sprinters, 2 for fast shamblers, 3 for shamblers (default in most modes), or 4 for random speeds. You can change this without starting a new world.





Project Zomboid