Water Usage Calculator

Calculate household daily water usage and monthly cost from habits and household size.

By Konstantin Iakovlev · Updated September 2026 · Source: EPA WaterSense — Statistics and Facts

Daily Usage

167 gal

Monthly Cost

$25.01

Per Person/Day

56 gal

Water Usage

Daily Usage167 gallons
Monthly Usage5,001 gallons
Monthly Cost (est.)$25.01
Your Per Person/Day56 gal
US Average82 gal/person/day

Use the Water Usage Calculator above to calculate your results. Enter your values and see instant results — all calculations run in your browser.

Disclaimer: This calculator is for informational purposes only. Results are estimates based on the information you provide and the assumptions described on this page.

How It Works

Knowing where your water actually goes is the first step toward using less of it. The estimate here ties your daily household consumption and monthly bill to the habits and household size you enter, turning vague usage into numbers you can act on.

Consumption is built up activity by activity from fixed figures: 17 gallons per shower (about 2.1 gallons a minute for 8 minutes), 30 gallons per laundry load and 6 per dishwasher run (both spread over the week), five 1.6-gallon toilet flushes and 8 gallons of sink use per person per day, and 10 gallons for each minute of lawn watering per week, spread over seven days. The daily total is multiplied by 30 for the month and priced at a flat $0.005 per gallon ($5 per 1,000 gallons), which leaves out sewer and fixed charges. Your gallons per person are compared with 82 gallons a day, the per-person home use figure EPA's WaterSense program cites from USGS.

Laundry and dishwashing quietly consume far more than most people guess, which is where efficiency upgrades earn their keep; low-flow showerheads and toilets cut usage noticeably. Outdoor watering is the other blind spot, and in a yard of any size it can quietly dwarf everything happening indoors.

Example: A Three-Person Household's Water Use

  1. 1 Inputs (the calculator's defaults): 3 people, 3 showers a day, 5 laundry loads and 4 dishwasher runs a week, and 30 minutes of lawn watering a week.
  2. 2 Daily gallons: showers 3 × 17 = 51; laundry 5 × 30 / 7 = 21.4; dishwasher 4 × 6 / 7 = 3.4; toilets 3 × 5 × 1.6 = 24; sinks 3 × 8 = 24; lawn 30 × 10 / 7 = 42.9. Total: 166.7 gallons a day, shown as 167.
  3. 3 Monthly: 166.7 × 30 = 5,001 gallons, priced at $0.005 a gallon = $25.01. Per person: 166.7 / 3 = 56 gallons a day, below the 82-gallon U.S. figure the calculator compares against.
  4. 4 Lawn watering is about a quarter of this household's use even at 30 minutes a week. EPA WaterSense puts outdoor use at more than 30% of household water on average and as much as 60% in arid regions.

Source: EPA WaterSense — Statistics and Facts · Last updated: September 2026

Frequently Asked Questions

How much water does the average American household use per day?
EPA's WaterSense program says the average American family uses more than 300 gallons of water a day at home, roughly 70% of it indoors, and that each American uses an average of 82 gallons a day at home. Toilets are the largest indoor use at nearly 30%, and showers account for nearly 17%.
How much does water cost per month?
EPA WaterSense puts the average family's water costs at more than $1,000 a year and says retrofitting with WaterSense fixtures and ENERGY STAR appliances can save more than $380 a year. Local rates vary widely, and sewer charges, often based on water use, can add substantially to the total.
What uses the most water in a home?
Toilets are the largest indoor use, nearly 30% according to EPA WaterSense, and showers nearly 17%. Outdoor use averages more than 30% of household water and can reach 60% in arid regions. WaterSense says installing water-efficient fixtures and appliances can cut use by at least 20%, and fixing easily corrected leaks saves about 10% on water bills.

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