Zombie Infection Simulation v2.3 - The Original

Created by Kevan Davis, August 2003

To view the zombie infection simulation, you'll need to install Java.

Simulation Rules

Zombies are grey, move very slowly and change direction randomly and frequently unless they can see something moving in front of them, in which case they start walking towards it. After a while they get bored and wander randomly again.

If a zombie finds a survivor standing directly in front of it, it bites and infects them; the survivor immediately joins the ranks of the undead.

Survivors are pink and run five times as fast as zombies, occasionally changing direction at random. If they see a zombie directly in front of them, they turn around and panic.

Panicked survivors are bright pink and run twice as fast as other survivors. If a survivor sees another panicked survivor, it starts panicking as well. A panicked survivor who has seen nothing to panic about for a while will calm down again.


  • Press g to toggle between grey and green zombies.
  • Press s to alter the simulation speed.
  • Press space to uninfect all but one zombie.
  • Press z or reload the page to reset to a new city.
  • Press + and - to adjust population (this also resets the city).
  • Press p to toggle complete panic (as in v1).

(You'll need to click on the Java window before it'll accept keypresses.)


The Zombie Infection Simulation was built with Processing (for which full source code is available). Adapted versions of this code include:-

And oh, I also wrote Urban Dead.

Last updated 27th August 2003 - infection direction bug fixed (thanks to Brian Birmingham and Dirk-Lüder Kreie for noticing it), green zombie option added, population adjustment enabled.