Home Energy Calculators
Dripping faucet cost.
A faucet that drips once a second wastes more than 3,000 gallons of water a year, according to the US EPA. Enter your drips per minute and your water price to see gallons wasted and what it costs, with the water heating cost added if it is a hot tap. Runs in your browser; nothing is sent or stored.
Your numbers
Result
Fill the form and press Calculate.
Worked example
A faucet dripping 30 times a minute makes 30 x 525,600 = 15,768,000 drips a year. At 0.36 mL each that is 5,676 litres, or 1,500 US gallons a year (about 4.1 gallons a day). At an example price of $8 per 1,000 gallons the water costs $12.00 a year. If it is a hot tap and the heater adds 70°F with electricity at $0.15 per kWh, heating adds $38.51, for $50.51 a year, or $4.21 a month. Example inputs: replace them with your own.
How it works
Gallons per year = drips per minute x 525,600 minutes x millilitres per drip / 1,000 / 3.785. The default drip volume of 0.36 mL is not a measured standard: it is the volume that reproduces the EPA's figure that one drip a second wastes more than 3,000 gallons a year (31,536,000 drips in a year). Drip size depends on the faucet and water pressure, so the best check is to catch a count of drips in a measuring cup. Water cost is gallons / 1,000 x your price. For a hot tap, heating energy is gallons x 8.345 lb x temperature rise / 3,412 Btu per kWh (or 100,000 per therm, per US EIA) divided by efficiency.
Not covered. Sewer charges are only included if you add them to the water price. A drip that comes and goes will waste less than the steady-drip result.
Sources and basis (pages opened 2026-10-08): US EPA WaterSense, Fix a Leak Week; US EIA, What is a British thermal unit (Btu)?.
This is a planning estimate and not professional plumbing, electrical or financial advice. Rates, fixtures and equipment vary, so confirm important decisions with your utility, the manufacturer or a licensed professional.
FAQ
How much does a dripping faucet cost per year?
It depends on the drip rate and your water price. One drip a second wastes more than 3,000 gallons a year per the US EPA; multiply the gallons by your price per 1,000 gallons, then add heating if it is a hot tap.
How many drips make a gallon?
With the default of 0.36 mL per drip, about 10,500 drips make a US gallon. Real drips vary, so measure yours if precision matters.
Does a hot water drip cost more?
Yes. You pay for the water and for the energy that heated it, which the calculator adds when you choose a hot-water tap.
How do I count drips per minute?
Count the drips for 30 seconds and double the number, or time 10 drips and scale up.
Is a small drip worth fixing?
Often yes. The EPA says old and worn washers and gaskets frequently cause faucet leaks, and that common household leaks can often be fixed with a few tools and hardware that pay for themselves in water savings.