Irrigation Calculators
Crop water requirement, drip system run time and the cost of pumping water.
Water is money – measure it
Whether you irrigate from a canal, a tube well or a farm pond, knowing how much water the crop actually needs helps you avoid both stress and waste. Over-irrigation leaches nitrogen, raises pumping bills and can bring up salinity; under-irrigation cuts yield at the stages where it matters most.
- Irrigation Water Requirement Calculator – uses the FAO method (ET0 × crop coefficient) to estimate water need in mm and litres, with pumping time.
- Drip Irrigation Calculator – emitters, lateral length, system flow and how long to run the drip each day.
- Irrigation Cost Calculator – electricity or diesel cost per irrigation and for the season.
A useful rule to remember: 1 mm of water spread over 1 square metre is exactly 1 litre. So 50 mm over one acre (4,047 m²) is about 2,02,000 litres.
Frequently asked questions
Where do I find ET0 values for my area?
Daily reference evapotranspiration (ET0) is published by many state agricultural universities and IMD agro-met advisories. As a rough guide, ET0 in much of India ranges from 3–4 mm/day in winter to 7–9 mm/day in peak summer.