Which formula is used?

This tool applies head = acres × forage × utilization ÷ (weight × intake × days). Every figure updates live as you change the inputs.

The maths follows the stated formula precisely, but the answer is an estimate that depends on the values you enter and on rules that can change.

Can I export the result?

Yes — use the PDF button to download a branded multi-page report with your inputs, results and working.

Biology

Cattle Per Acre Calculator

Estimate how many cattle a pasture can carry for a grazing period.

Your inputs

Change any value — everything updates instantly.

Pasture area ac

Grazeable acres.

Forage available lb DM/ac

Measured or estimated dry matter.

Utilization %

Share you plan to graze.

Animal weight lb

Average head.

Daily intake % BW

About 2.5% of body weight.

Grazing days days

Length of season.

Try an example

Cattle supported

13.9 head

This means the pasture supports about 13 head for the period.

Cattle supportedHead per acreUsable forage

Slow motion1×13.9 head

What you are seeing

Each bar grows to show a result for your inputs.

The top bar is the main answer: 13.9 head.

Change forage available (now 2,500) and the bars update instantly.

Head per acre

0.35 head/ac

Total ÷ acres.

Usable forage

50,000 lb DM

Acres × forage × utilization.

Result explanation: Cattle supported

13.9 head.

Real-life comparison: With forage available 10% higher, the answer would be 15.28.

Low, normal or high? Use this as an estimate based on the stated formula.

Graph and details

How the result changes with forage available

How to read this chart: The line shows the result across a range of values. The dot marks your input.

What this calculator does

Estimate how many cattle a pasture can carry for a grazing period.

What your result means

This means the pasture supports about 13 head for the period.

Forage estimates vary.

The formulas

Matches forage supply to animal demand.

1. Stocking rate

head = acres × forage × utilization ÷ (weight × intake × days)

Symbols

DM: Dry matter (lb)

Why this formula works

Matches forage supply to animal demand.

Unit check

Units match on both sides ✓

Worked example

40 × 2,500 × 0.5 = 50,000
÷ (1,200 × 0.025 × 120)
= 13.9 head

Common mistakes

Grazing 100% of forage.

Working for your numbers

Supply = 50,000 lb
Demand/head = 3,600 lb
= 13.89 head

This means the pasture supports about 13 head for the period.

Frequently asked questions

Utilization?

Take half, leave half is a common rule.

Drought?

Re-measure forage.

Calves?

Count as animal units.

Hay?

Adds supply.

Symbols and assumptions

DM: Dry matter (lb)

Uniform pasture.

Sources and review

Reviewed 2026-09-25 · Next review 2027-09-25

Calculating stocking rateUniversity of Nebraska–Lincoln

Important limitation. Forage estimates vary.

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