All calculators
Twelve tools covering the arithmetic that comes up on septic, drainage and earthwork jobs. Search by name, or jump to a category below.
12 calculators
- septicSeptic Tank VolumeConvert the inside dimensions of a rectangular or cylindrical tank into gallons, liters and cubic feet.
- septicDaily WastewaterMultiply occupants by an editable gallons-per-person-per-day figure to see daily, weekly and annual flow.
- septicPerc RateConvert an observed water-level drop and elapsed time into minutes per inch and inches per hour.
- septicDrain Field AreaDivide a daily design flow by a soil loading rate you supply to get a rough absorption area in square feet.
- drainageFrench Drain GravelWork out the gravel volume for a French drain trench, with the perforated pipe subtracted and a waste allowance added.
- drainagePipe SlopeTurn a measured run and vertical drop into slope percentage, fall per foot and a 1-in-X ratio.
- drainagePipe DropEnter a pipe length and a target slope to get the total fall you need to set between both ends.
- drainageDrainage StoneVolume and tonnage for a rectangular bed of drainage stone, with an editable density and waste allowance.
- drainageRainfall RunoffEstimate how much water a roof, driveway or lawn sheds during a given rainfall, in gallons and cubic meters.
- earthworkTrench VolumeLength, width and depth to cubic feet, cubic yards and cubic meters for any straight trench.
- earthworkExcavation VolumeIn-place and loose volumes for a rectangular or circular dig, including a swell allowance for hauling.
- earthworkSoil WeightTurn a soil or aggregate volume into pounds, US tons and kilograms using an editable material density.
Septic
Tank capacity, household flow, percolation timing and absorption area estimates.
- Septic Tank Volume CalculatorConvert the inside dimensions of a rectangular or cylindrical tank into gallons, liters and cubic feet.
- Daily Wastewater CalculatorMultiply occupants by an editable gallons-per-person-per-day figure to see daily, weekly and annual flow.
- Perc Rate CalculatorConvert an observed water-level drop and elapsed time into minutes per inch and inches per hour.
- Drain Field Area EstimatorDivide a daily design flow by a soil loading rate you supply to get a rough absorption area in square feet.
Drainage
French drains, pipe grade, stone quantities and runoff volumes.
- French Drain Gravel CalculatorWork out the gravel volume for a French drain trench, with the perforated pipe subtracted and a waste allowance added.
- Drain Pipe Slope CalculatorTurn a measured run and vertical drop into slope percentage, fall per foot and a 1-in-X ratio.
- Pipe Drop CalculatorEnter a pipe length and a target slope to get the total fall you need to set between both ends.
- Drainage Stone CalculatorVolume and tonnage for a rectangular bed of drainage stone, with an editable density and waste allowance.
- Rainfall Runoff CalculatorEstimate how much water a roof, driveway or lawn sheds during a given rainfall, in gallons and cubic meters.
Earthwork
Trench and excavation volumes plus soil and aggregate weights.
- Trench Volume CalculatorLength, width and depth to cubic feet, cubic yards and cubic meters for any straight trench.
- Excavation Volume CalculatorIn-place and loose volumes for a rectangular or circular dig, including a swell allowance for hauling.
- Soil Weight CalculatorTurn a soil or aggregate volume into pounds, US tons and kilograms using an editable material density.