Calculates the total daily and seasonal irrigation water volume for any field based on crop type, field area, evapotranspiration rate, and effective rainfall — so you can size supply infrastructure accurately from day one.
Determines the precise water consumption of specific crops at each growth stage using FAO crop coefficients (Kc), local climate data, and planting density — giving you a day-by-day water demand profile throughout the season.
Works out the minimum holding tank capacity for a drip irrigation system by combining daily water demand, dripper flow rate, emitter spacing, and a configurable safety buffer — eliminating the guesswork from tank procurement.
Determines the total on-farm storage capacity needed to bridge dry periods by accounting for irrigation demand, livestock consumption, rainfall harvesting potential, and the number of days of supply buffer required.
Calculates total water volume consumed by an overhead sprinkler system based on sprinkler flow rate, coverage area, run time, and number of zones — helping you benchmark efficiency and reduce water bills.
Computes daily and weekly water needs for your herd or flock by species, head count, average body weight, ambient temperature, and production stage — so water troughs and storage tanks are never undersized.
Determines the required pump power (kW/HP) and flow capacity for your irrigation system by factoring in total dynamic head, pipe friction losses, elevation change, and target delivery flow rate at the field.
Sizes holding tanks specifically for field-scale irrigation by combining field area, application rate, irrigation cycle length, and refill frequency — ensuring continuous supply even when mains or bore water delivery is intermittent.
Estimates daily and monthly water demand inside enclosed growing structures by factoring in floor area, crop type, ventilation rate, humidity targets, and evapotranspiration — giving you accurate storage and supply recommendations.
Water Planning Tools for Farmers, Growers & Agronomists
Agricultural water management sits at the intersection of productivity and sustainability. Too little water and yields collapse; too much and you waste a finite resource, raise input costs, and risk waterlogging or root disease. The nine tools in this category give smallholders, commercial growers, and irrigation engineers a single, reliable calculation layer — from estimating seasonal crop water budgets aligned with FAO-56 evapotranspiration standards, to right-sizing drip tanks, field storage dams, livestock troughs, and greenhouse supply systems. Whether you're planning a new drip scheme in an arid region, scaling up a greenhouse operation, or working out how many kilolitres of on-farm storage will see your herd through a dry summer, every calculator here produces actionable numbers in plain language — no agronomy degree required.
How to Choose the Right Irrigation Calculator
1 Start with crop or livestock water demand
Before sizing any tank or pump, establish how much water your operation actually consumes. Use the Crop Water Need Calculator for field crops or the Livestock Water Requirement Calculator for animal operations. These outputs become the baseline inputs for every other tool in this category.
2 Match your delivery method to a sizing tool
Drip and sprinkler systems have very different tank and pump requirements. Use the Drip Irrigation Tank Size Calculator if you're running emitter-based systems, or the Sprinkler Water Usage Calculator for overhead coverage. For large open fields, the Field Irrigation Tank Sizing Calculator handles hectare-scale planning directly.
3 Size your pump to match delivery, not just demand
A tank that's large enough is useless if the pump can't move water fast enough to meet peak demand windows. After establishing your volume needs, run the Irrigation Pump Size Calculator to confirm the required flow rate and pressure head — factoring in pipe runs and elevation.
4 Plan for dry season buffer with farm storage
For operations relying on rainfall, bore water, or intermittent mains supply, the Farm Water Storage Calculator lets you set a buffer of days and calculates the total storage needed to ride out supply gaps — accounting for both irrigation and stock water simultaneously.
5 Use the comparison table below to narrow your choice
Each calculator is optimised for a specific scenario. The table below maps common farming situations to the most relevant tool.
| Your Situation | Best Calculator | Key Output |
|---|---|---|
| Sizing a new drip scheme | Drip Irrigation Tank Size | Tank capacity (litres) |
| Planning seasonal crop water | Crop Water Need + Irrigation Requirement | mm/day, L/season |
| Cattle or sheep water supply | Livestock Water Requirement | L/day per animal |
| Choosing pump for field irrigation | Irrigation Pump Size | kW / HP rating |
| Whole-farm storage planning | Farm Water Storage | Total kL required |
| Greenhouse growing operation | Greenhouse Water Usage | L/day & monthly |
| Overhead sprinkler audit | Sprinkler Water Usage | L/session, cost |
Pro tip: For mixed farming operations, start with the Farm Water Storage Calculator and work backwards — it accepts combined irrigation and livestock demand as a single input, so you can aggregate all your sub-calculations into one final storage figure.
Frequently Asked Questions
Irrigation water requirements depend on your crop type, field area, evapotranspiration (ET) rate, soil type, and local rainfall. Our Irrigation Water Requirement Calculator lets you enter these factors and outputs the total daily and seasonal water volume needed, so you can size your tank, pump, and supply infrastructure accordingly. As a reference point, most field crops in warm climates require 4–8 mm/day of irrigation during peak growing periods.
A drip irrigation tank needs to hold at least one full day's irrigation volume, plus a 20–30% safety buffer. Use our Drip Irrigation Tank Size Calculator: enter your field area, crop type, dripper flow rate, and emitter spacing. The tool calculates daily water demand and recommends the minimum tank capacity in litres or gallons. For farms with unreliable water supply, we recommend sizing for two to three days of autonomous supply.
Livestock water requirements vary widely by species, body weight, ambient temperature, and production stage. As a rough guide: dairy cattle need 80–150 litres/day, beef cattle 40–70 L, sheep 4–10 L, goats 5–12 L, and poultry 0.2–0.5 L per bird. These figures increase by 20–40% in hot weather above 30°C. Our Livestock Water Requirement Calculator accounts for herd size and temperature to give you a precise daily and weekly volume for storage sizing.
Pump size depends on the required flow rate (litres per hour) and the total dynamic head — which includes elevation difference, pipe friction losses, and end-pressure at the emitters. Our Irrigation Pump Size Calculator takes your field area, pipe length, elevation change, and target flow rate and outputs the required pump power in kilowatts or horsepower. As a rough rule, a 1 kW pump can typically deliver 3,000–5,000 L/hr against 20–30 m of total head.
Greenhouse water needs depend on floor area, crop density, ventilation rate, and humidity targets. Enclosed environments typically use 3–8 litres per square metre per day for leafy crops, and 8–15 L/m² for fruiting plants like tomatoes or cucumbers. Our Greenhouse Water Usage Calculator factors in your greenhouse dimensions, crop type, and climate control setup to give you accurate daily water demand and storage recommendations for both heated and polytunnel structures.
Drip irrigation is typically 30–50% more water-efficient than overhead sprinkler systems because water is delivered directly to the root zone with minimal evaporation or wind drift. However, sprinklers are better suited for germination, frost protection, and dense plantings like turf or grain crops. Use our Sprinkler Water Usage Calculator to estimate exact consumption for your system, then compare it against drip totals from our Drip Tank Calculator to make the most cost-effective choice for your crop type and climate.