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Pea Gravel Calculator

This page opens with the density set to 1.7 tonnes per cubic metre, the common figure for pea gravel, because the rounded stone packs closer than angular crushed rock and a tonnage worked at plain gravel's 1.5 will come up short. Type the area, a rectangle or a circle, and the depth you are laying, in feet and inches or metres and centimetres, and read the cubic yards, the tonnes, the US short tons and the whole bags at once. The density stays a field: if your yard quotes their own figure for the grade you are buying, type it over the top and every number follows it.

20 ft10 ft2 in
20 ft by 10 ft at 2 in1.60 t1.23 cu yd · 0.94 m³ · 33.33 cu ft1.77 US tons at 1.70 t/m³ · 41 bags of 40 kg or 71 of 50 lb
Shape
Length
Width
Depth
Material
Density t/m³
Units

The density is the figure everything after the volume depends on, so it is a field and not a hidden constant. Loose gravel is about 1.5 tonnes per cubic metre, pea gravel a little heavier, and wet stone heavier again: if your yard quotes a weight per cubic yard, divide it by 0.765 to get tonnes per cubic metre and type it in. Switching between imperial and metric rewrites what you already typed into the other system, to four decimals, rather than clearing it, and the volume is then worked from the figures on the screen.

Optional. Nothing is stored, and no rate is suggested: prices are local and they move.
  • A small border12 ft by 3 ft at 2 in
    0.22 cu yd, 0.29 t
  • A driveway30 ft by 10 ft at 4 in
    3.70 cu yd, 4.81 t
  • A circular bed8 ft across at 3 in
    0.47 cu yd, 0.60 t
Exact about the volume, honest about the weight. Length by width by depth, converted between feet, yards, metres and inches without rounding until the last step, so the volume is exact. It cannot know your supplier's density or how far the stone settles once it is walked on, so the tonnage and the bag count are estimates from a density you can change. There is no price list, no supplier and no delivery charge here, because a rate is the one input that would go stale; type your own above and the page multiplies it. Depth is a measurement you enter and this page reads back to you: what goes under a surface that carries weight is groundworks, and it is not something a quantity calculator should decide.

Common questions

How much does a cubic yard of pea gravel weigh?
At the 1.7 tonnes per cubic metre this page opens with, a cubic yard of pea gravel weighs 1.30 tonnes, which is 1.43 US short tons or about 2,865 lb. Loose gravel at 1.5 gives 1.15 tonnes for the same yard and crushed stone at 1.6 gives 1.22, so the material you pick moves the answer by around a tenth either way. The figure is for dry stone: a load that has sat in the rain weighs more, and no calculator can see that from your measurements.
How much pea gravel do I need for a patio or a path?
Two inches of pea gravel over 20 feet by 10 feet is 1.23 cubic yards, which at 1.7 comes to 1.60 tonnes, 1.77 US tons or 41 bags of 40 kg. A hundred square feet at the same depth is 0.62 cubic yards and 0.80 tonnes. Pea gravel is usually laid about 2 inches deep on a walking surface: deeper is harder to walk on, since rounded stone shifts underfoot rather than binding, which is also why an edge restraint matters more with pea gravel than with crushed stone.
Is pea gravel heavier than crushed stone?
By volume, usually yes, and this page opens at 1.7 tonnes per cubic metre for pea gravel against 1.6 for crushed stone. The rounded, well graded stones nest closer together and leave less air between them, so a cubic yard holds more rock. The gap is small enough that a supplier's own figure should win over both: the buttons set a starting point, and the field is there to be typed over.
How many bags of pea gravel are in a ton?
Twenty-five 40 kg bags to a metric tonne, and forty 50 lb bags to a US short ton, whatever the stone is: the bag counts follow from the weight, not from the material. What the material changes is how many bags a given area takes. A circular bed 8 feet across at 3 inches deep is 0.47 cubic yards, which at 1.7 is 0.60 tonnes, or 16 bags of 40 kg, where the same bed in loose gravel at 1.5 would be 0.53 tonnes and 14 bags. Every count here rounds up, because half a bag is not something a shop sells.
Where does 1.7 come from, and should I trust it?
It is a commonly published density for dry, loose pea gravel, and it is a starting point rather than a measurement of your stone. Grade, screening and moisture all move it, which is why the number is on the screen instead of hidden inside the sum. If the yard you are buying from quotes a weight per cubic yard, divide it by 0.765, since that is how many cubic metres a cubic yard is: 1.30 tonnes per cubic yard is 1.70 tonnes per cubic metre. Type their figure in, because it is the one that will be on the ticket.

Length by width by depth, converted between feet, yards, metres and inches without rounding until the last step, so the volume is exact. It cannot know your supplier's density or how far the stone settles once it is walked on, so the tonnage and the bag count are estimates from a density you can change.