Leak Drip Loss Calculator
Count how often a faucet drips and see the gallons, liters, and dollars that adds up to over a day, a month, and a year.
Estimated loss
How the estimate works
A drip has no fixed size, so this calculator uses the one the USGS Water Science School states for its drip calculator: 1/4 milliliter a drip, about 15,140 drips to a gallon. One drip a second (60 a minute) is then 21.6 liters, about 5.7 gallons, a day. Your drip rate is multiplied out to liters and gallons a day, then projected to a month and a year. EPA WaterSense puts the same one-drip-a-second faucet at more than 3,000 gallons a year, so a big-dropped faucet can waste more than this shows.
If you enter a rate (add the water and sewer charges per 1,000 gallons from a recent bill; a bill priced per CCF is per 748 gallons), the tool also estimates what that drip is costing you annually — often enough on its own to justify a $2 washer and ten minutes with a wrench.
Frequently Asked Questions
How is drips-per-minute converted into gallons?
It uses the drip size the USGS Water Science School states for its own drip calculator: one drip is taken as 1/4 milliliter, about 15,140 drips to a gallon or 4,000 to a liter. USGS says there is no scientific definition of a drip's volume and chose that size after measuring kitchen and bathroom sink faucets. Your drips per minute times 1,440 minutes times 0.25 mL gives liters a day, then gallons, a month and a year. EPA WaterSense puts a one-drip-a-second faucet at more than 3,000 gallons a year, so larger drops do happen; this tool shows the lower of the two published figures.
How do I count my own drip rate?
Time drips for 10 or 15 seconds with a phone stopwatch and multiply up to a per-minute rate (a 10-second count times 6, or a 15-second count times 4). Counting for a full minute directly is more accurate if the drip is irregular.
Is a slow drip really worth fixing?
At one drip per second the USGS drip size works out to about 5.7 gallons a day, roughly 2,080 gallons a year from a single faucet, and EPA WaterSense puts it at more than 3,000. A worn washer or O-ring is usually a cheap, quick fix, which is why leak repair is one of the highest-value, lowest-effort water-saving projects in a home.
Does this account for a running toilet or a pipe leak?
No — this tool is specifically for a dripping faucet or fixture measured in drips per minute. A running toilet or a hidden pipe leak wastes water on a different scale entirely and is usually found by checking the water meter when nothing in the house is running, or by adding a few drops of food coloring to the toilet tank to see if it seeps into the bowl without flushing.
Educational estimate only. Actual drop volume varies by fixture and wear; if a leak is significant or won't stop, shut off the supply valve and call a licensed plumber.