Find your rate on your utility bill; $8–$16 per 1,000 gallons is a typical combined US range.
This leak is costing you about
How the math works
Drip math uses the U.S. Geological Survey’s standard estimate of roughly 15,140 drips per gallon. Count your faucet’s drips per minute and the gallons-per-year figure follows directly — a one-drip-per-second faucet wastes over 2,000 gallons a year, all of it billed. Toilet numbers use the ranges plumbers and the EPA’s WaterSense program cite: a silent flapper leak loses around 30 gallons a day, an audibly running toilet around 200, and a stuck-open fill valve can pass 600 or more. Your combined water and sewer rate converts gallons to dollars — most utilities bill sewer on metered water, so every wasted gallon is charged twice, which is why the combined rate is the honest one to use.
The fix is usually under $15
The frustrating part of leak math is how cheap the cure is. A faucet drip is typically a worn washer or cartridge seal. A running toilet is almost always the flapper or the fill valve — both inexpensive parts that need no special tools. Start with our guide to a toilet tank that won’t fill properly, and if your toilet has other symptoms, the won’t-flush and bubbling-when-flushed guides cover the related failure modes. For supply-side leaks around a water heater, read the water heater leaking guide before assuming the tank itself has failed.
The dye test: confirm a silent toilet leak in 15 minutes
Put a few drops of food coloring in the toilet tank and wait fifteen minutes without flushing. Color appearing in the bowl means the flapper is letting water through — a leak you’d otherwise never hear, costing you every day. It’s the single highest-value fifteen-minute test in home plumbing.
Frequently asked questions
My water bill seems high but I can’t find a leak — now what?
Turn off every fixture and appliance that uses water, then check your water meter. If the low-flow indicator is still turning, something is drawing water — toilets and irrigation lines are the usual suspects, and underground service-line leaks are the expensive one worth ruling out with a plumber.
Does a hot-water drip cost more?
Yes — a dripping hot tap wastes the energy used to heat that water on top of the water itself, so the true cost runs higher than this calculator shows.
Is anything I enter saved?
No — the calculator runs entirely in your browser. Estimates are based on national figures; see our disclaimer.