Science & Environment
Evapotranspiration (Simplified Penman-Monteith) Calculator
Estimate reference evapotranspiration using a simplified Penman-Monteith form with temperature, radiation and wind.
Your inputs
Change any value to update the result instantly.
Reference evapotranspiration
4.66 mm/day
Annual estimate
1,701 mm/year
Temperature range
16 °C
Wind adjustment factor
1.04
Formula and working
ET0 ≈ (0.0023 × (Tmean + 17.8) × √(Tmax − Tmin) × Ra) adjusted with wind factor
- 1
Collect the inputs
Mean temperature = 22 °C; Max temperature = 30 °C; Min temperature = 14 °C; Extraterrestrial radiation = 30 MJ/m²/day; Wind speed at 2m = 2 m/s
- 2
Apply the formula
ET0 ≈ (0.0023 × (Tmean + 17.8) × √(Tmax − Tmin) × Ra) adjusted with wind factor
- 3
Result
Reference evapotranspiration = 4.66 mm/day
Frequently asked questions
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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