Topsoil Calculator for New Lawns, Topdressing and Repairs
Enter your project dimensions
Lawn work here is decided by a window rather than a season. Seeding waits for the cooler end of the year, sod goes down through the warm months, and either way the job needs a stretch of dry days: topsoil spread on soaked red clay smears instead of raking, and a pile left out through a thunderstorm gets a third heavier to shovel. Book the delivery for the week you intend to spread, then work out the quantity below.
What a tonnage estimate cannot see in a red clay yard
Every calculator on the internet assumes the ground under your lawn is flat and the layer on top of it is even. Piedmont yards are rarely either. Years of runoff leave the high side thin and the low side deep, so a figure worked out from one depth reading will be wrong in both directions at once.
Two more things the arithmetic cannot know. The first is what the subgrade does: topsoil laid straight onto sealed clay behaves like a bathtub with the plug in, so the surface needs breaking up an inch or so before anything goes on it, and loosened ground swallows slightly more than the flat number suggests. The second is the finished grade, which should fall away from the house across the first stretch of yard rather than sit level. Treat the result as a good order, not a measurement.
Yards for ordering, tons for what lands on the drive
Topsoil is sold by the cubic yard, so the yardage is the figure to write down. The tons line tells you what the truck is carrying, and on this site screened topsoil is figured at about 2,200 lb a cubic yard, which is 1.10 tons.
The chain is short. Length times width in feet gives square feet. Multiply by the depth in inches and divide by 12 for cubic feet. Divide by 27 for cubic yards. Multiply by 1.10 for tons. The 2,200 lb is the weight of the material as sold; rain moves the weight and not the volume, so a yard soaked through is heavier to shovel while still covering exactly the area it was going to cover. Order dry and pick your week.
Entering a lawn that is cut in two by the drive
Rectangle asks for a length and width in feet. Circle asks for a diameter, which suits a ring of lawn around a tree or an island bed. Multiple areas holds up to five pieces, so a front lawn split by the driveway goes in as two rectangles and comes back as a single yardage.
Depth is entered in inches, from 0.25 to 24, which means a topdressing goes in as 0.5 rather than as a fraction. Choose the material, decide on the box marked add 5% extra for compaction and spillage, and the result appears as cubic yards, tons and cubic feet, with an option underneath to have the figures emailed rather than written on your hand.
Topdressing, overseeding, a new lawn: the depths that matter
A quarter to half an inch is a topdressing, raked in until the grass tips still show. Half an inch to an inch suits overseeding. A new lawn, seeded or sodded, wants 4 to 6 inches over a subgrade that has been loosened first. A flower bed takes about 6 inches blended into what is underneath rather than laid on it.
Anything deeper belongs to a different order. Raised vegetable beds want 12 inches of blended growing mix, and that is what the soil calculator is for.
Seeding a new back lawn, then feeding the front one
Three made-up jobs, written out so the math is visible.
A new back lawn, 45 by 28 feet, at 4 inches over loosened ground. That is 1,260 square feet. 1,260 x 4 / 12 = 420 cubic feet, which is 15.56 cubic yards, or 17.11 tons. With the 5% box ticked it reads 16.33 yards and 17.97 tons.
A topdressing across 3,100 square feet of established front lawn at half an inch. 3,100 x 0.5 / 12 = 129.17 cubic feet, or 4.78 cubic yards, which is 5.26 tons. Ten times the depth would be ten times the order, which is why the depth box deserves more thought than the tape does.
A low strip beside the walk, 32 by 5 feet, filled 3 inches to bring it back level. 160 x 3 / 12 = 40 cubic feet, or 1.48 cubic yards, which is 1.63 tons.
The low corners that eat the last yard
Tick the 5% box. On the back lawn above that is about three-quarters of a yard, which is roughly what the low corners and the edges along the beds will take once you start raking and find the ground is not as even as it looked.
Order a little over rather than a little under. Spare topsoil disappears into repairs within two weeks, while coming up short leaves a bare patch that has to wait for a second delivery, and on a seeded lawn that patch will show all season. Settle the new surface lightly rather than stamping it: a footprint pressing in about half an inch is about right.
Where this page stops and the bed and fill tools start
Screened topsoil is natural soil with the stones, roots and clods taken out, and it belongs on lawns and finish grade. It is listed here as Top Soil.
If the job is a planting bed or a raised box, Garden Soil blends compost into topsoil and is sized on the soil calculator. If the ground has to come up more than a few inches, that lift is structural and belongs in Fill Dirt, sized on the dirt calculator, with topsoil kept for the top 4 to 6 inches where roots actually grow. Once your yardage looks right, open the product page to set quantity and a date. Delivery is arranged at checkout by ZIP code, so leave the truck a firm spot to tip on and keep the pile off the lawn you are about to seed.
Common questions
Half the lawn is a bank running down to the street. Does that change the square footage?
Yes, and it is worth walking. Measure the length down the face of the bank rather than the flat distance you would see on a plan, because that sloping surface is what has to be covered. On a steep bank, also work at the lower end of the depth range so the new soil does not slide off before the grass roots hold it.
The back lawn is an L around the deck. Does that go in as one shape?
Use multiple areas and enter each leg as its own rectangle, touching but not overlapping at the corner. Give each leg its own depth if one side has settled more, which by the deck it usually has, and the tool returns one total.
Should the mulched strip along the fence be left out of the lawn area?
Leave it out if it is staying as a bed. Measure to where the grass will actually finish. The exception is a strip you are converting back to lawn, which needs the same depth as the rest and should go in as a second area so you can see what it costs you.
I have to fill before I finish. How do I order the two layers?
As two calculations. Work out the fill to bring the grade up to about 4 to 6 inches below your finished level, then run this tool for the topsoil cap at that depth. Ordering the whole lift as topsoil is expensive and it will keep settling, because topsoil is not made to hold a grade.
The front lawn has no straight edge anywhere. What length and width do I put in?
Square it off. Take the longest run for the length, measure the width in three or four places and use the middle figure, then check the corners you have cut off against the corners you have added. Anything left over on a lawn-sized area is comfortably inside the 5% box.
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Lawn math done? Soil's on us to deliver.
Screened topsoil by the cubic yard, free delivery across Georgia.
