gizmobench

Fill Soil Calculator

A hole 3 feet by 3 feet and 2 feet deep takes 18 cubic feet of fill, which is 0.67 cubic yards, 510 litres, or 12 bags of the 1.5 cubic foot size. This page always opens in fill mode, with that hole in the fields the first time you land on it, so put your own length, width and depth over it and the cubic feet, the cubic yards, the litres and the bag count follow at once. It measures a hole, a trench or a low patch the way you dug it, as a rectangle, and it keeps the cubic yards figure on the screen next to the bags, because past about a yard a bulk load usually stops the bag counting being worth doing. The bag size is a field here rather than a brand we assumed, and it works in feet and inches or metres and centimetres.

24 in of soil3 ft × 3 ft fill
Soil needed3 ft by 3 ft at 24 in
Cubic feet18.000.67 cu yd · 510 litres12 bags at 1.5 cu ft, rounded up
Mode
Length ft
Width ft
Depth in
Bag cu ft
Units
Common bag sizes

The bag size is a field because it is the one number a brand decides: bagged soil and compost are sold at anything from 0.75 to 3 cubic feet, and 40 litre and 50 litre sacks work out at 1.41 and 1.77 cubic feet. Type what is printed on yours and the count follows. Switching between feet and metres 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.

  • A 4 by 8 raised bed10 in of mix, /soil-calculator/raised-bed
    26.67 cu ft · 18 bags
  • A hole to fill3 ft by 3 ft, 2 ft deep, /soil-calculator/fill
    18.00 cu ft · 12 bags
  • A 12 in round pot10 in of mix, /soil-calculator/pot
    0.65 cu ft · 1 bag
Exact on the shape you describe, and it says so about the rest. Exact arithmetic on what you enter: length by width by depth, or the cylinder formula for a pot, converted without rounding until the last step. It cannot know how far soil settles after its first watering, how much room root balls take, or what a brand actually puts in a bag. There is no price here and no supplier, and no allowance is folded in behind the figure: if you want a margin for settling, raise the depth a little and watch the number move.

Common questions

How much soil do I need to fill a hole?
Measure it as a box: length, width and depth, in feet and inches or metres and centimetres. A hole 3 feet square and 2 feet deep is 18 cubic feet, 0.67 cubic yards, and 12 bags of 1.5 cubic feet, or 18 bags of 1 cubic foot, or 9 of 2. A narrower stump hole 2 feet square and 3 feet deep is 12 cubic feet and 8 bags. Depth is the field that moves the answer fastest, since it multiplies the whole area, so measure the deepest part and the shallowest and split the difference if the bottom is uneven.
How do I work out a trench?
A trench is a long thin rectangle, so it is the same three fields. A run 20 feet long and 3 feet wide brought up 4 inches is 20 cubic feet, 0.74 cubic yards and 14 bags of 1.5. A 30 foot trench 2 feet wide filled 6 inches deep is 30 cubic feet, 1.11 cubic yards and 20 bags. At that point the yard figure is the one to quote a supplier, because 20 bags is heavy work and usually dearer than a delivered yard.
How much topsoil do I need to level a low spot in a lawn?
Treat the patch as a rectangle around it and use the average depth you are bringing it up by, not the deepest point. A 10 foot by 10 foot dip raised 2 inches is 16.67 cubic feet, 0.62 cubic yards and 12 bags of 1.5. A 10 by 2 foot strip needing 6 inches is 10 cubic feet and 7 bags. Levelling is usually done in thin passes rather than one thick one, so if you plan two passes of an inch each, run the figure at one inch and double the bags.
What if the hole is not a rectangle?
Split it into two or three rectangles, run each one and add the answers. That is more honest than averaging an odd shape into a single box, and it takes a few seconds because every field recomputes as you type. For something genuinely round, a hole for a post or a large pot, the Pot page uses the cylinder formula on a diameter and a height instead. What this page will not do is guess at a shape you have not described: it multiplies the three numbers you give it and prints the cubic yards, the litres and the bag count under the answer.
Should I order fill by the bag or by the cubic yard?
Both figures come from the same measurement and sit side by side, so you can compare. A cubic yard is 27 cubic feet, which is 18 bags of 1.5 or 27 bags of 1, and most suppliers quote loose fill by the yard. Under about half a yard, bags are usually simpler; over a yard, a delivered load is normally both cheaper and less carrying. This page holds no prices and names no supplier, because a price is local and it moves, so the quantity is what it gives you and the quote is yours to get.

Exact arithmetic on what you enter: length by width by depth, or the cylinder formula for a pot, converted without rounding until the last step. It cannot know how far soil settles after its first watering, how much room root balls take, or what a brand actually puts in a bag.