About this Tool

This calculator is based on a discrete-time simulation that runs day by day, rather than a continuous differential equation model. It simulates the outcome of a zombie apocalypse by calculating the results of daily encounters.

The simulation uses the following steps for each day:

1. Encounters: The number of encounters is calculated as:
   Total Encounters = Zombies × Attacks per Zombie
   (This value is capped at the total number of living humans).
2. Fights: In this model, every encounter is a fight. The number of fights won by each side is determined by the Human Fighting Skill.
3. Human Losses: Humans who lose a fight are killed.
   Human Deaths = Fights Won by Zombies
4. New Zombies: A percentage of killed humans are reanimated, based on the Transformation Probability.
   New Zombies = Human Deaths × Transformation %
5. Zombie Losses: Zombies who lose a fight are "killed." However, a percentage may survive due to the Zombie Resurrection Rate.
   Zombie Deaths = Fights Won by Humans × (1 - Resurrection %)
6. Update Populations: The populations of humans, zombies, and the "removed" (permanently dead) are updated for the next day.

The simulation runs for the specified duration or until one side is wiped out.