Evapotranspiration (ETo & ETc)Engineering

Reference Evapotranspiration (ETo & ETc) Crop Water Demand Calculator

Calculate reference evapotranspiration (ETo mm/day), crop coefficient (Kc), actual crop water consumption (ETc = ETo * Kc), and daily hectare water demand in m³/day following FAO-56 standards.

Calculator Inputs

Live Real-Time
ha
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Calculated ResultEvapotranspiration (ETo & ETc)

Total Daily Farm Water Requirement (m³/day)

262.5m³/day

Actual Crop Evapotranspiration (ETc mm/day)

5.25 mm/day

Water Demand per Hectare (m³/ha/day)

52.5 m³/ha

Total Daily Water (Liters/day)

262,500 L/day

Precision Irrigation Scheduling: Calibrated FAO-56 evapotranspiration models optimize crop yield.

Evapotranspiration Metrics

Hectare m³
52.5 m³(17%)
Total m³/day
262.5 m³(83%)

Detailed Calculation Breakdown

Crop ETc (mm)
5.25 mm
Hectare m³
52.5 m³
Total m³/day
262.5 m³

Calculation Methodology

Crop Evapotranspiration: ETc = ETo * Kc. Daily Hectare Water Volume (m³/ha/day) = ETc (mm) * 10 (since 1 mm depth across 1 hectare = 10 m³).

Important Legal & Educational Disclaimer

This hydrological agronomy tool computes FAO-56 Penman-Monteith crop water requirements.

This calculator is designed for educational and informational purposes only based on public statutory frameworks. The outputs do not constitute binding financial, tax, or legal advice. We assume no liability for decisions made based on these estimations. Always verify with the relevant official authorities or a certified professional advisor.

Frequently Asked Questions

The globally accredited physical benchmark method for estimating reference evapotranspiration (ETo) using temperature, solar radiation, vapor pressure, and wind speed.
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