Project Zomboid SandboxVars & difficultySet zombies, loot & XP freely

Published on August 4, 2026 · last updated on October 21, 2026

The servertest_SandboxVars.lua file

The game rules are in servertest_SandboxVars.lua in the same folder as servertest.ini. It is plain Lua and contains numerous pairs of values. You edit it via the config editor in the web interface or via WebFTP/SFTP - a server restart is required after changes.

Presets as a starting point

Instead of starting from zero, use a preset and fine-tune it:

• Apocalypse - the default: slow but deadly zombies, scarce loot, real survival.
• Survivor - somewhat fairer: respawning resources and more leeway.
• Builder - focus on building: few zombies, relaxed gathering and construction.

Adjusting zombie behavior

The most exciting block is the zombie properties. Important values:

• Zombies - population density (Insane to None).
• Speed - sprinters, fast shamblers or slow shamblers.
• Strength / Toughness - strength and resilience.
• Sight / Hearing / Cognition - perception and intelligence.

That way, you can build any scenario from "cosy" to "nightmare".

Loot, XP & time

With LootRespawn and the rarity of individual loot categories, you control how scarce supplies are. XpMultiplier speeds up or slows down skill progress, and DayLength sets the length of a day. For community servers, moderate increases (a little more loot, slightly higher XP) are popular to make getting started more pleasant.

LootRespawn deserves special attention, because it shapes the character of a server more than any zombie setting. If the value is 0 - the Apocalypse default - looted items are gone for good. On a server that is supposed to run for months, that means the map is empty at some point and new players have no chance. A respawn every few weeks keeps the world alive without giving up the survival character.

What can still be changed afterwards

Most values take effect after a restart even on a running world - zombie speed, loot rates, XP multipliers, day length. A few things, on the other hand, are fixed by Project Zomboid during world generation and are not touched afterwards. Above all, this includes the original distribution of the zombie population across the map.

In practice, this means: you can make the zombies faster or stronger at any time, but an area that has already been explored is not repopulated retroactively. If you want to change the density fundamentally, you need a fresh save - you can back up the old one beforehand via WebFTP or SFTP, see Create backups.

Also note: the file name depends on the server name. If your server is not called servertest, the file is named differently too. If you edit the wrong file, nothing changes - and you look for the error in the wrong place.

Three combinations that work

Instead of weighing every value individually, it helps to orient yourself by the gameplay feel you want:

• After-work server. Apocalypse as a basis, XpMultiplier at 2 to 3, loot slightly increased, DayLength at 2 hours. Anyone who only plays two evenings a week still makes progress without it feeling handed to them.
• Long-term community. Apocalypse unchanged, but LootRespawn activated and the zombie population slightly below default. That keeps the map playable for months, and new members still find something.
• Building round. Builder as a basis, zombie speed set to shamblers, XP for crafting skills high. The focus is then on the base, not on survival.

What you do not control with the SandboxVars are access and network - PvP, password, slots and mods are separately in servertest.ini. Keeping the two files cleanly apart saves the most common confusion in server configuration. How to add content to the world is explained in Install mods.

Frequently asked questions