Stealth and noise in Project Zomboid

There are two channels: vision and hearing. Darkness and fog cut how far zombies see. Rain and fog also cut how far they hear, but by much less. Cover from cars, fences and walls helps you stay out of sight. Zombies each roll their own hearing, speed and vision, so two zombies in one street can react differently. The difficulty is set in the sandbox settings, and the basics of the infected are on zombies.

Sneaking is the only skill that lowers your chance of being seen. It also shortens the distance zombies can spot you from and quiets your crouch steps. Lightfooted lowers footstep noise whether you walk, run or crouch. Nimble now also reduces footstep noise across all movement, not only in combat.

Crouching through an empty area gives little or no Sneaking XP and costs more endurance than walking.

Footstep noise multiplies together. These are the factors one guide lists for 42.19 (one source).

Lightfooted by level: 0.99, 0.90, 0.79, 0.71, 0.65, 0.59, 0.52, 0.45, 0.37, 0.30, 0.20 for levels 0 to 10. A community calculation puts a maxed build at roughly 99% quieter than the base for crouch steps, but that is a ceiling, not a guarantee. You are still audible up close, and doors, fights, vehicles and guns override stealth.

Point costs can change between patches, so check traits and occupations at character creation.

One guide gives the formulas for 42.19 (one source, and its combined sight formula is ambiguous).

That makes full fog alone 0.90 on hearing, and full fog plus full rain 0.57. Rain does more to hearing than fog does. Two sandbox options matter: Fog Cycle (Normal, No Fog, Endless Fog) and Maximum Fog Intensity. Players cannot clear fog with an item, so you wait it out. Another guide says weather and night reduce vision only, not hearing, which does not match the formula above, so treat the hearing numbers with care.

Gun radii come from one guide and are approximate. They scale with the Firearm Noise Multiplier (default 1.0). Generators make continuous noise even after the power cuts, vehicle engines and horns carry far, and a helicopter will track you outdoors and draw zombies with its engine noise; get inside and out of sight. Curtains and sheets block line of sight through windows but do not reduce noise. Light is not a special lure, but a lit window at night shows your silhouette. Global /all chat does not attract zombies. Generator details are on generators.

Redistribute Hours is how long before zombies move into empty parts of a cell, which is why a cleared street can fill up again.

Opinion Do your loud jobs, such as hammering, generators and gunfire, well away from where you sleep. Dress the windows facing the street before you light a room. Train Lightfooted and Sneaking early near a single slow zombie with an escape route behind you, and stop the moment one notices you. Build a kill zone away from the base rather than fighting at the door. See the first week guide for the early order of play.