Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
Head the pasture supports
28.8
Acres per cow
6.95
Animal unit months available
224.4
Usable forage (lb)
175,000
Grazing days at that stocking
180
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter pasture acres.
- 2Enter forage production (lb/acre).
- 3Enter harvest efficiency (%).
- 4Enter average cow weight (lb).
- 5Enter grazing season (months).
- 6Read your head the pasture supports on the right — it updates as you type.
- 7Hit Share to keep the scenario or send it to someone.
About this calculator
Match herd demand to forage supply using animal unit months. Enter pasture acres, forage production, and utilization to see how many head the ground actually carries.
Worked example
Using the values the calculator loads with:
Inputs
- Pasture acres: 200
- Forage production: 2500 lb/acre
- Harvest efficiency: 35 %
- Average cow weight: 1300 lb
- Grazing season: 6 months
Results
- Head the pasture supports: 28.8
- Acres per cow: 6.95
- Animal unit months available: 224.4
- Usable forage (lb): 175,000
- Grazing days at that stocking: 180
What each field means
Inputs
- Pasture acres
- The pasture acres used in the calculation. Starts at 200 so you have a working example on load.
- Forage production (lb/acre)
- The forage production used in the calculation, measured in lb/acre. Starts at 2500 lb/acre so you have a working example on load.
- Harvest efficiency (%)
- The harvest efficiency used in the calculation, measured in %. Starts at 35 % so you have a working example on load. Accepted range: 10–70 %.
- Average cow weight (lb)
- The average cow weight used in the calculation, measured in lb. Starts at 1300 lb so you have a working example on load.
- Grazing season (months)
- The grazing season used in the calculation, measured in months. Starts at 6 months so you have a working example on load.
Results
- Head the pasture supports
- Returned as a decimal number and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Acres per cow
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Animal unit months available
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Usable forage (lb)
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Grazing days at that stocking
- Returned as a decimal number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Why only 35% utilization?
The take-half-leave-half rule, adjusted for trampling and fouling. Continuous grazing lands near 25–35%; intensive rotation can reach 50–60%.
What is an animal unit?
A 1,000 lb cow with calf consuming about 26 lb of dry matter a day, or 780 lb a month.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Cattle Stocking Rate Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/cattle-stocking-rate
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/cattle-stocking-rate" target="_blank" rel="noopener">Cattle Stocking Rate Calculator — RevenueLab</a> (2026).</p>
Source: [Cattle Stocking Rate Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/cattle-stocking-rate) (2026).