Build 42: everything new

Build 42 is the biggest update in Project Zomboid's history. It reached the public Stable branch as 42.20 on July 29, 2026, and the current Stable version is 42.21 (September 28, 2026). Build 41 is still available on the legacy41 branch.

• Bigger. The map's surface area has doubled.
• Rebuilt towns. Riverside, West Point, Rosewood, Fallas Lake, Muldraugh, Ekron and Dixie now have unique buildings, consistent landscaping and town-specific styles. The rest of the towns, then Louisville, get the same treatment next.
• New towns. Ekron, Irvington and Brandenburg, plus smaller spots.
• New places. A Wild West tourist town, a docked steamboat, Irvington Speedway, a lakeside guesthouse and an abandoned sanatorium.
• Scale. 1,400 unique buildings and 20,000 new tiles, up from 15,000 tiles in Build 41.
• Endless wilderness. Randomised forest lies beyond the map edges, so you can live off the grid.
• The Exclusion Zone was redesigned to feel lived-in.

See every town on our Knox Country map.

• Basements, bunkers and panic rooms appear under suitable houses, and they change from run to run.
• Louisville skyscrapers reach up to 32 floors, full of zombies.
• Door and light states are randomised, and some houses have already been looted when you arrive.
• You can scrub grime off walls.
• XL and XXL trees drop more wood. Right-click while driving to hide their overhang.
• Vehicles come in location-specific liveries, such as police cars, sponsored race cars and work vans, each with its own loot.
• World seeds control basements, zombie distribution and wilderness. You can save and share a seed.
• A new spawn map makes hordes more urban, using noise for randomness.

Full detail in our farming & food guide.

• New crops include corn, peas, tobacco and herbs such as rosemary.
• Crops grow in realistic time, with best and failure-prone planting months.
• New tools for pulling stumps and scything grass.
• No crop can be sown in December or January.

• New skills: masonry, carving, knapping and blacksmithing.
• Workstations link crafting to surfaces and devices.
• Choose your ingredients and search recipes by what you have or what you want.
• Batch crafting and right-click shortcuts.
• Melee weapons in parts: handle and head have separate condition, blades have sharpness, heads can fall off, and broken weapons can become crude clubs.
• Construction: clay and stone walls, new wooden walls, drying racks, food preservation and shelters.

Recipes, levels and stations are in the crafting guide.

• Aim at a precise spot on a zombie. Accuracy depends on panic, stress and your Aiming skill.
• New 3D models, animations, muzzle effects, ammo types and sounds for every gun.
• Six new guns arrived in 42.15: the JS-14 rifle, JS-3T tactical shotgun, L92 carbine, L94 rifle, MSR7T tactical rifle and Trapper carbine. Lever-action rifles and shotguns got reload animations in 42.18.
• Firearm loot was reworked to fit Knox Country's history, and guns can jam in Apocalypse.
• Melee swings can cause muscle strain.

Every gun with its calibre is in the item database.

• Hundreds of new clothing items, including Halloween masks, SWAT uniforms, headwear and craftable armour.
• Modular armour pads stack with your clothes.
• New containers: stickered backpacks, trauma bags, ALICE rigs, gun cases, craftable satchels, tents, and sleeping bags that attach to backpacks.
• Mannequins store and swap outfits.
• Place items anywhere on a tile, and hang guns and crafted weapons on walls.
• Cartons pack canned food, nails and ammo into one item.
• Mix liquids into combinations.

• Occupations and traits were rebalanced, with more starting skill levels.
• New occupation: Rancher.
• Renamed: Fire Officer is now Firefighter, Angler is Fishing Guide, and the Wilderness Knowledge trait is Bushcrafter.
• Hunter starts with +1 Tracking, Park Ranger with +1 Carving, and Welders start with Welding recipes.
• New traits: Artisan, Target Shooter and Tinkerer.
• Only Veteran grants Desensitized on 42.19.

See professions and starting skills in the beginner's guide.

Compare every setting in game modes compared.

• Inventory and every timed action now run on the server; the client handles visuals only.
• Anti-cheat checks for speed, hits, no-clip and inventory.
• Dozens of desync fixes and a reworked network state to stop stuck animations.
• Servers hold up to 254 players since 42.20.3, and admins can still join a full server.
• Ping is shown for each player, and servers can show or hide coordinates.
• You get a warning when joining a server on a different game version, and driving at high ping is smoother since 42.21.
• The server browser can hide modded, full or empty servers and sort by ping or players.

Setting one up? Read hosting a server.

• Mod manager: search, favourites, load order, dependencies and incompatibilities, and presets you can share via the clipboard.
• Interface scales better on large monitors.
• Controllers: fully customisable bindings saved as shareable presets. Controller remapping arrived in 42.19.
• Lore: flyers, newspapers, book titles, TV and radio stations, annotated maps and random world stories.
• Languages added in 42.20: Czech, Indonesian, Spanish (Argentina) and Spanish (Mexico).

Build 42 is heavier than Build 41, especially with animals and big bases.

Laptop stutters? Make sure the game runs on the dedicated GPU, not the integrated one. Set it to high performance in the Nvidia or AMD control panel.

• Build 42 is the default on Steam now.
• To stay on Build 41: right-click Project Zomboid in your library, choose Properties, then Game Versions & Betas, and pick legacy41.
• To finish a 42.19 Unstable save: pick the 42.19 beta. 42.19 saves do not load in 42.20 or later.
• Build 41 saves do not carry over to Build 42.
• Most Build 41 mods need updating for Build 42. Add mods one at a time.
• The game's price went up when Build 42 launched, as it did with Build 41. It is still in Steam Early Access.

1. Hotfixes.
2. A patch of tweaks from player feedback, aimed mostly at the late game.
3. The mapping tools (WorldZed, TileZed) and AnimZed.
4. A full modding guide and mod community improvements.
5. A Build 42 Support Update through the rest of 2026: optimisation, modding support, and features that missed the Stable cut.
6. Ongoing multiplayer and controller work.

Follow every update in our patch notes and news.

• Dec 17, 2024 Build 42 opens on the Unstable branch after about three years of work. Single player only.
• Dec 11, 2025 42.13.0 brings multiplayer to Unstable.
• Mar 9, 2026 42.15: the four game modes and six new guns.
• Mar 31, 2026 42.16: occupations and traits reworked; Tinkerer and Target Shooter added.
• Apr 20, 2026 42.17: start in any Exclusion Zone town, skill VHS tapes.
• May 11, 2026 42.18: bigger water containers, sit-on-ground keybind, modding fixes.
• Jun 1, 2026 42.19: controller remapping.
• Jul 29, 2026 42.20: Build 42 goes Stable with the Map Glowup.
• Aug 2026 The Build 42 launch weekend pushed concurrent players past 103,000, beating the 2022 record of about 65,000.
• Aug 17, 2026 42.20.3: servers up to 254 players.
• Sep 28, 2026 42.21 Stable. From now on every update goes to Unstable first, then Stable.

• Only Lua mods are officially supported. Java mods run with the game's full power, so a bad one can compromise your PC. Use trusted authors and prefer the Workshop.
• First-person mods are not officially supported.
• In April 2026, 14 malicious music mods were removed from the Workshop. Uninstalling alone was not enough to clean them up.
• Several security holes were patched across Stable, Unstable and Legacy during 2026.
• Mods can write .json files, and mod recipes work in multiplayer.
• Community translation is back: over 1.3 million words in 29 languages.

Full story in our news.

The challenge list can change with patches. Read each tooltip on the challenge screen before you start.

Negative traits give you points to spend on positive ones. Values below are for Build 42.

Changed in 42.16 and 42.17: Cat's Eyes and Wakeful cost more, First Aider and Iron Gut cost less, Nutritionist costs 2, and Desensitized also blocks Discomfort.

• Tracking: footprints and droppings are visible at Tracking 0, twigs and fur at 2, and you can identify deer at Tracking 4.
• Trapping: six trap types. Traps only catch while you are away, and every trap needs fresh bait. Carrots are best for rabbits, cheese for mice.
• Fishing: look for ripples, fish at dawn or dusk, and use premium line for big fish. Fishing 10 gives a 50% chance of a big fish.
• Chum attracts fish, and baited nets only take chum.

Full tables in our tracking, trapping and fishing guides.

• Seasons change the weather and decide what you can plant.
• Hypothermia is real: dress for the cold. 42.20 fixed it killing players too fast.
• Water and power shut off on a timer set by your game mode. In Custom Sandbox, power can be disabled entirely.
• Lights only run on generator power when wired correctly; 42.20 fixed lights ignoring generators.
• Erosion slowly reclaims the world, more slowly since 42.16 in Apocalypse, Outbreak and Rising.
• The "zombie count before deletion" sandbox limit rose from 500 to 5,000 in 42.20.

Build 41 went Stable on December 20, 2021, and was the main version of Project Zomboid until July 2026. It is still playable on the legacy41 branch, and The Indie Stone still patches it for security: the latest is 41.78.21 (August 26, 2026).

Build 42 replaced Survivor and Builder with Outbreak, Rising and Extinction. Apocalypse stayed, and is now the canon mode.

1. Back up your whole Zomboid folder.
2. If you run a server, tell your players the world will be wiped.
3. Export servertest.ini and servertest_SandboxVars.lua for reference. Many settings were renamed or changed defaults, so start from a fresh Build 42 config.
4. Check every mod on its Workshop page for Build 42 support. Start with a minimal list and add mods one at a time.
5. Update: steamcmd +login anonymous +app_update 380870 validate +quit.
6. To keep an old world going instead: +app_update 380870 -beta legacy41 validate.

There is no way to convert a Build 41 world. Start fresh, or keep it on legacy41.

• Nov 8, 2013 Project Zomboid launches in Steam Early Access.
• Dec 20, 2021 Build 41 goes Stable with multiplayer and Louisville. Concurrent players jump from about 3,000 to over 35,000.
• 2022 A record of about 65,000 players at once.
• Dec 17, 2024 Build 42 opens on Unstable.
• Dec 11, 2025 Build 42 multiplayer arrives on Unstable with 42.13.0.
• Jul 29, 2026 Build 42 goes Stable. Build 41 moves to legacy41.
• Aug 2026 A new record: over 103,000 players at once.
• Aug 26, 2026 Build 41.78.21 security patch.
• Sep 28, 2026 42.21 Stable.

The game is still in Early Access. No full release date has been announced.