Estimate crop yields, livestock output & peasant feeding capacity for a medieval manor — historically grounded for 12th–14th century England
The medieval English manor was the basic unit of agrarian organisation from the Norman Conquest (1066) until the Black Death (1348–51). A "hide" — roughly 120 acres — was the traditional unit of land sufficient to support one free peasant family. The open-field three-field rotation system, spreading from the 11th century, divided the manor's arable land into three great fields: winter grain (wheat/rye), spring grain (barley/oats), and fallow. Domesday Book (1086) records around 5,000 manors in England, averaging 5–10 hides each. Medieval wheat yields of around 3:1 to 5:1 seed-to-harvest ratio (roughly 6–12 bushels per acre) were far below modern yields of 40+ bushels per acre. The lord typically claimed one-third of all production through tithes, labour services, and mill tolls.
Enter your manor's size in hides (1 hide ≈ 120 acres), select the soil quality for your region, and set the number of peasant households. Choose your crop rotation system and adjust the sliders to set the percentage of arable land under each crop type — wheat, rye, barley, and oats must total 100%. Input your livestock numbers, pick a harvest quality modifier, and click Calculate Manor Output. The tool instantly shows total caloric production, per-household feeding capacity, the lord's tithe share, seed reserves, and a detailed crop-by-crop breakdown.
Understanding medieval food production isn't just an academic exercise — it reveals the extraordinary precariousness of life before industrialised agriculture. A typical 5-hide manor supporting 20 peasant households was operating with almost no buffer: one bad harvest (a 0.75× modifier) could tip a community from adequacy into hunger; two consecutive failures meant famine.
Historians, game designers building historically grounded strategy games, teachers preparing unit plans, and historical fiction writers all benefit from this calculator. If you're running a tabletop RPG set in medieval Europe, you can use these numbers to determine whether a siege will starve a village in months or years. If you're writing a novel, you'll understand why a drought in July caused genuine terror. The numbers also explain medieval social structures: the lord's one-third tithe wasn't arbitrary greed — it was the fixed extraction rate that left just enough for peasants to survive and sow the next season's seed.
A five-hide manor producing a normal wheat harvest could expect roughly 1,800–2,400 bushels of total grain — enough for around 20–25 households if the seed corn and lord's share are deducted first.
This calculator uses historically documented yield ratios and unit conversions from 12th–14th century English manorial records (including the Bolton Priory accounts and Walter of Henley's Husbandry, c.1280).
Arable acres: 1 hide × 120 acres × rotation efficiency (3-field = 0.667 productive, 2-field = 0.50, intensive = 0.85)
Crop yield (bushels): Acres under crop × yield per acre × soil modifier × weather modifier
Seed reservation: 25% of harvest retained for next year's sowing — a historical constant regardless of yield.
Lord's tithe: 33% of net production (after seed), reflecting typical 13th-century manorial extraction.
Livestock caloric contribution: Cattle = 1,200 kcal/day (milk + occasional slaughter); Sheep = 300 kcal/day (milk, wool, meat); Pigs = 400 kcal/day (autumn mast slaughter estimate).
1 bushel of wheat ≈ 1,080,000 kcal (60 lbs × ~18,000 kcal/lb of flour equivalent).
A hide was the standard English land unit from the Anglo-Saxon period, theoretically defined as the amount of land sufficient to support one free peasant family for a year. In practice it ranged from 40 to 240 acres depending on region and soil quality, but 120 acres became the standard administrative definition by the time of the Domesday Survey in 1086. This calculator uses 120 acres per hide as its base.
The two-field system left half the manor's land fallow each year to restore fertility — only 50% was productive. The three-field system rotated winter crops, spring crops, and fallow across three fields, meaning 67% of the land was productive each year. This 33% increase in productive acreage, combined with the nitrogen-fixing effect of spring legumes (peas and beans), dramatically increased total output and helped support the population growth of the 12th–13th centuries.
The caloric values are based on modern nutritional data for heritage grain varieties and adjusted downward ~15% to account for medieval milling inefficiencies and post-harvest losses (spoilage, vermin). Livestock figures are estimates based on zooarchaeological evidence and contemporary agricultural treatises. They should be treated as reasonable approximations for educational and gaming purposes rather than precise historical measurements.
Absolutely — that's one of this tool's primary use cases. The output gives you realistic per-village food stocks, siege duration estimates, and famine trigger thresholds. For a medieval fantasy setting, a village of 20 households can feed itself for roughly 12–18 months on stored grain before requiring a new harvest, assuming normal conditions. A famine-year result showing under 75% feeding capacity means your village is already in crisis by midwinter.