Feed Budget (Days of Feed) Calculator

Estimate how many days a paddock will feed a mob from pasture mass, area, stock numbers and intake.

Grazing days = available dry matter ÷ daily demand = (pasture mass − residual) × area ÷ (stock × intake per head). 1,000 kg/ha usable over 100 ha for 500 head eating 12 kg/day lasts about 17 days.

Calculator

Pasture mass (kg DM/ha)Standing dry matter now (kg of dry matter per hectare).Target residual (kg DM/ha)Dry matter you want left when stock come off.Paddock area (ha)Number of stock (head)Intake per head (kg DM/day)Daily dry matter intake per animal.

Grazing days available

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How it works

Only the feed above your target residual is usable, so subtract the residual first, then multiply by area for total kilograms available. Divide by the mob's total daily intake to get how many days they can graze before hitting the residual.

Worked example

(2,500 − 1,500) × 100 = 100,000 kg DM available. Demand = 500 × 12 = 6,000 kg DM/day. 100,000 ÷ 6,000 ≈ 17 days.

Assumptions & limitations

Ignores pasture growth during grazing (conservative in spring, accurate in dry spells), trampling/wastage and changes in intake as quality drops. Estimate pasture mass with a plate meter or calibrated visual assessment.

Frequently asked questions

Why subtract a residual instead of grazing to the ground?

Leaving a residual (often 1,200–1,800 kg DM/ha for many pastures) protects regrowth, soil cover and animal intake. Grazing below it slows recovery and total annual production, so only the feed above it counts as usable.

Does this include grass growing back?

No — it's a snapshot of standing feed. In active growth you'll get more days than shown; in dry conditions the figure is close. For rotations, re-measure each shift.

What intake should I use?

Dry matter intake is roughly 2–3% of liveweight per day, so a 500 kg cow eats about 10–15 kg DM. Lactating or growing stock are at the higher end. Use a figure that matches your class of stock.

Last updated 21 June 2026

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