Agriculture & Forestry
Crop Water Requirement Crop Coefficient ($ET_c = K_c \times ET_0$) Sizer
Calculate crop water requirement crop coefficient ($et_c = k_c \times et_0$) using the stated engineering or scientific relationship and adjustable field inputs.
Preparing your result…
What this calculator does
Calculates Crop Water Requirement Crop Coefficient ($ET_c = K_c \times ET_0$) Sizer using the formula verified against the cited source.
What your result means
An estimate from the inputs you enter, within the scope stated below — not advice.
Formula
ETc = Kc × ET₀
The step-by-step working for your own numbers appears with the result above and in the PDF report.
Frequently asked questions
Symbols and assumptions
- Inputs
- The values entered in the fields above
- • Under standard well-watered conditions, crop evapotranspiration ETc=Kc×reference ETo. Kc is dimensionless; ETc and ETo have the same depth/time units.
Sources and review
Reviewed 2026-10-18 · Next review 2027-04-18
- • FAO56 single-crop-coefficient method. Kc must match crop, growth stage, climate and the reference-ETo method. ETc is not automatically irrigation demand: effective rainfall, soil-water storage, stress and application efficiency require additional calculations.
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.
Quick reference
| Scenario | Crop coefficient Kc | Reference evapotranspiration (mm/day) | Crop water requirement |
|---|---|---|---|
| Worked example | 1.05 | 5 | 5.25 mm/day |
| Half the amounts | 0.53 | 2.5 | 1.325 mm/day |
| Double the amounts | 1.5 | 10 | 15 mm/day |
Need the full picture? Get the detailed PDF report with charts, tables, formulas and working steps.
Reviewed 2026-10-18 · Next review 2027-04-18
Report a mistake or request an improvement
Tell us if a formula, unit, explanation, or result needs attention. Your message will include this calculator’s name and page.
Related calculators
Agricultural Drainage Tile Spacing & Depth (Hooghoudt Equation)
Calculate agricultural drainage tile spacing & depth (hooghoudt equation) using the stated engineering or scientific relationship and adjustable field inputs.
Agricultural Lime (ENM / CCE) Neutralizing Requirement Sizer
Calculate agricultural lime (enm / cce) neutralizing requirement using the stated engineering or scientific relationship and adjustable field inputs.
Center Pivot Irrigation Water Application Depth (Inches/Hour)
Calculate center pivot irrigation water application depth (inches/hour) using the stated engineering or scientific relationship and adjustable field inputs.
Corn Grain Moisture Shrinkage & Drying Cost Sizer
Calculate corn grain moisture shrinkage & drying cost using the stated engineering or scientific relationship and adjustable field inputs.
Crop Seed Planting Population per Acre & Row Spacing Sizer
Calculate crop seed planting population per acre & row spacing using the stated engineering or scientific relationship and adjustable field inputs.
Drip Irrigation Emitter Flow Rate & Block Run-Time Sizer
Calculate drip irrigation emitter flow rate & block run-time using the stated engineering or scientific relationship and adjustable field inputs.
Namaste! Did this Crop Water Requirement Crop Coefficient ($ET_c = K_c \times ET_0$) Sizer help you?
Aapka ek click humein behtar banata hai. Just tap a star, no sign-in, no typing.