Estimate the volume and tonnage of any stockpile (conical piles, windrows, and bunkers) with material density built in. Free, no signup. For piles that aren't textbook-shaped, there's a more accurate way below.
Pile shape
Estimated volume
768yd³
Estimated tonnage
1,075tons
Truckloads (14 yd³)
55
Geometric estimate for a perfect cone; real piles typically vary ±20–40%.
Cubic feet: 20,735 · Cubic meters: 587.1
This calculator uses the standard geometric formulas surveyors have used for decades. Pick the shape that best matches your pile, measure its footprint and height, and multiply by your material's loose bulk density to convert cubic yards to tons.
Conical piles (single drop point, stacker or conveyor):
V = (π × r² × h) ÷ 3, where r = diameter ÷ 2
Windrows and elongated piles (triangular prism with two half-cone ends):
V = (w × h ÷ 2) × (L − w) + (π × (w ÷ 2)² × h) ÷ 3
Bunkers, bays, and bins (footprint times average depth):
V = length × width × average depth
These formulas assume a perfectly shaped pile on a flat base. Real stockpiles have scalloped faces from loader cuts, uneven crowns, and sloped floors, which puts walk-around geometric estimates at roughly ±20–40% error. That's fine for a gut check; it's why measured inventory is the standard for month-end reconciliation and audits. For the full comparison of measurement methods (phone scanning, drones, fixed LiDAR, and survey services), read our guide to the best ways to measure stockpile volume.
Measure the pile's footprint and height, then apply the geometric formula for its shape: a conical pile is (π × r² × h) ÷ 3, an elongated windrow is the triangular cross-section times length plus conical ends, and a bunker is length × width × average depth. Divide cubic feet by 27 for cubic yards, then multiply by the material's density to get tons.
Geometric formulas assume a perfectly shaped pile on a flat base, so expect ±20–40% on real stockpiles with scalloped faces, uneven crowns, and sloped ground. For inventory that feeds a balance sheet, a measured survey (phone scan, drone flight, or fixed sensors) is the standard; a well-captured scan lands within a few percent.
Loose gravel runs about 2,800 lb per cubic yard, so one cubic yard is roughly 1.4 tons. Density varies with moisture and gradation, so use your scale-house numbers when you have them.
Most aggregates, coal, and grain settle between 30° and 40°. At a typical 37°, pile height is roughly 0.38 × base diameter. Wood chips and fibrous materials stack steeper; wet sand shallower.
Scan any pile with your phone and get its true volume in minutes: one lap around the pile, accurate to within a few percent, no formulas or assumptions.
