ONI Ranch Calculator

Lifespan (cycles)
Fertile stage (cycles)
Space required
Cycles/egg (after happiness)
Harvest eggs/life
Harvest eggs/cycle
Ranch critters
Ranch space
Ranch calories
Ranch Feed (kg/cycle)
Ranch Output (kg/cycle)


This tool is intended to be used to calculate the necessary ranch size in critters at steady state in order to produce a required number of harvestable critters.

The user selects (a) the critter the wish to ranch (b) the feed they will provide it and (c) the number of critters they wish to harvest each day. Based on this the tool's primary output is the ranch size (in critters and tiles) required to produce this harvestable output.

Two further user inputs are "Rancher Skill" which effects the length of the groomed buff and therefor how frequently the critters must be groomed; and "Cracking Eggs", if you are harvesting your ranch for meat then leave this unchecked. If you are however harvesting the eggs themselves (for egg shells for example) then check this box. This will increase the size of the ranch required as one egg in each lifetime can not be cracked in order to maintain the size of the ranch.

How users harvest the output is up to them; either still as eggs for raw eggs and egg shell, or once hatched for meat. If one intends to harvest for meat, we recommend using the Food Calculator first to determine the amount of meat required. The food calculator links through to the ranch calculator once you know which critter and how much of that critter needs to be harvested.


  • Critters are assumed to be tamed and kept happy at all times; tamed & happy critters are required in order to produce harvestable critters. Without the accompanying +900% bonus to egg production a ranch with harvestable excess critters is not possible.
  • Critters are assumed to never be impacted by confined/cramped/overcrowded debuffs that effect egg production. Accordingly all eggs produced are assumed to be instantly moved out of the ranching space.
  • Critters only begin producing eggs after their 5 cycle stage of being a juvenile.
  • The number of harvestable eggs/critters produced in a critter's lifetime is one less than total possible number of eggs produced rounded down to the nearest whole number; one egg must be used to maintain the ranch size.
  • The ranch size is rounded up to the nearest whole number providing some contingency to the above strict assumptions.
  • Using incubators has no impact on the output of the ranch once it reaches steady state (though they would help you get there faster).

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