Septic System Help, Made Simple
Use our free calculator below to get a planning estimate for the right septic tank size for your home, based on bedrooms, occupants, soil type and garbage disposal use.
Septic Tank Size Calculator
Find a planning estimate for your home in under a minute. No signup, no cost.
Garbage disposal used regularly?
Regular disposal use adds solids — plan for a larger tank or more frequent pumping.
Planning estimate only. Method: bedroom minimums commonly seen in many US codes (1 bed: 750 gal, 2 bed: 750–1,000 gal, 3 bed: 1,000 gal, 4 bed: 1,250 gal, 5 bed: 1,500 gal, 6 bed: 1,750 gal; for 7+ bedrooms, add 250 gal per bedroom over 6), checked against a 150 gallons per bedroom per day design flow. Drainfield size needs a percolation test. County and state rules govern.