Water Calculators

Water Weight & Planning Calculators

Calculate how much water weighs, then plan the real-world load. Use these calculators for pools, water tanks, aquariums, bottles, trailers, rain barrels, RV tanks, leaks, rainwater, wells, and irrigation.

Editable assumptions Copy and print results Clear safety boundaries

Browse by task

Choose a water task

Start with a primary calculator, then use the smaller tools for common products, sizes, and planning questions.

Weight & conversion

Get a direct water-only answer, then add density, containers, equipment or planning margin.

Water Weight CalculatorVolume, density, total project weight and common presets
Gallons to poundsLiters to poundsCubic feet of waterSaltwater weight

Pools, spas & aquariums

Plan filled weight, people, equipment, fill time, heating and operating cost.

Pool Water Weight PlannerShape, water depth, people, fill time and placement load
Hot tub load & costAquarium setup weight15-foot round pool18-foot round pool24-foot round pool75-gallon aquarium

Storage, transport & emergency

Choose containers, calculate loaded weight, compare payload and build an emergency plan.

Water Tank Weight CalculatorFill level, tank, equipment, footprint and entered rating
Emergency water storageRV fresh-water payload55-gallon drum275-gallon IBC330-gallon IBCBottled water supply

Bills, leaks & efficiency

Turn meter movement and abnormal bills into gallons, cost, evidence and repair payback.

Water Leak Cost & High Bill AnalyzerMeter test, drips, toilets, unexplained usage and cost
Hot tub operating costPool fill costDelivered water costRainwater savings

Rainwater & outdoor use

Measure irrigation demand, match rainwater supply, reduce runoff, and compare water-saving upgrades.

Rainwater Harvesting PlannerStorm capture, tank sizing, garden use, overflow and payback
Irrigation audit & costRain barrel load275-gallon IBC loadOutdoor leak costDaily demand & autonomy

Off-grid, wells & delivered water

Balance household demand, reliable inflow, pump runtime, deliveries and reserve storage.

Off-Grid Water Autonomy PlannerDaily demand, tank reserve, inflow and days of coverage
Well pump runtimeWater delivery & refillRainwater supplyEmergency reserve
1Start with the real taskChoose weight, supply, cost, storage or operating capacity—not just a number.
2Edit the defaultsReplace planning values with the label, manual, bill, meter or measured data you have.
3Check the next constraintUse the result to compare support, payload, storage, refill, cost or professional review.