Formula
Rectangular: bank volume = length × width × depth. Trapezoidal (sloped sides): bank volume = length × depth × (bottom width + top width) ÷ 2. Loose volume = bank volume × (1 + swell ÷ 100). Truck loads = loose volume ÷ truck capacity, rounded up.
Standard / source
Standard earthworks volume arithmetic. Swell (bulking) factors are soil- and moisture-dependent site values, not a universal code table — enter the factor measured or specified for your ground.
Worked example
Trench 10 m long × 2 m wide × 1.5 m deep: bank volume = 30.00 m³. At 25% swell, loose volume = 30.00 × 1.25 = 37.50 m³. At 6 m³ per truck: 37.50 ÷ 6 = 6.25, rounded up to 7 loads. These are the calculator's default inputs, so it shows 7 loads on load.
Safety note
Planning estimate only. This tool does not cover trench support, batter stability, underground services, dewatering or disposal rules — follow local excavation safety requirements and get the ground conditions checked before digging.