Starting a new lawn or raised bed? Guess the soil order wrong and you either pay for a half load or run out mid project. The Topsoil Calculator turns an area and a fill depth into cubic yards, tons, and bags.
It is built for gardeners and homeowners filling beds, leveling yards, or topping sod. You enter the length, width, and depth, then read the volume and weight.
Table of Contents
- What the Calculator Does
- How to Use It, Step by Step
- The Topsoil Volume Formula
- Worked Example
- How to Read the Results
- Depth, Weight, and Ordering Tips
- Limitations and Assumptions
- FAQs About the Topsoil Calculator
What the Calculator Does
The tool sizes soil for one rectangular area. Three inputs feed three results, shown after you press the button.
- Bulk Volume (Cubic Yards): the soil quantity for bulk delivery, with two decimals.
- Estimated Weight (Tons): an approximate weight for moist topsoil.
- 0.75 cu ft Bags: the count of 0.75 cubic foot volume bags, rounded up.
There is one button, Calculate Soil Volume and Weight. The tool also runs once when the page loads.
How to Use It, Step by Step
- Enter Area Length (Feet). The sample value is 30 feet.
- Enter Area Width (Feet). The sample value is 15 feet.
- Enter Fill Depth (Inches), such as 2, 4, or 6 inches.
- Press Calculate Soil Volume and Weight and read the three result cards.
The Topsoil Volume Formula
The tool finds the volume in cubic feet, converts it to cubic yards, then applies a weight and a bag size. One cubic yard holds 27 cubic feet.
Length x WidthxDepth / 12/ 27=Cubic Yardsx 1.07=Tons
- Area in square feet = length times width.
- Cubic feet = area times (depth divided by 12).
- Cubic yards = cubic feet divided by 27.
- Tons = cubic yards times 1.07, for moist topsoil.
- Bags = cubic feet divided by 0.75, rounded up.
Worked Example
Andre is filling a raised bed that is 20 feet long and 4 feet wide. He wants 6 inches of topsoil.
| Result | Calculation | Output |
|---|
| Cubic Feet | (20 x 4) x (6 / 12) | 40 cu ft |
| Bulk Volume | 40 / 27 | 1.48 Cu Yds |
| Estimated Weight | 1.481 x 1.07 | 1.59 Tons |
| Pre-packaged Bags | 40 / 0.75, rounded up | 54 Bags |
With the default 30 by 15 area at 4 inches, the tool shows 5.56 cubic yards, 5.94 tons, and 200 bags.
How to Read the Results
Bulk Volume is the number to give a soil yard for delivery. Bulk is usually cheaper than bags for large fills.
Estimated Weight helps you plan hauling and whether a truck can carry the load. Wet soil weighs more than dry.
0.75 cu ft Bags counts 0.75 cubic foot volume bags for small jobs. The count is rounded up so you have enough.
Depth, Weight, and Ordering Tips
A new lawn often needs 4 to 6 inches of topsoil for roots. A light top dressing over turf is closer to half an inch to one inch.
Soil weight shifts with moisture. The tool uses about 1.07 tons per cubic yard, which suits moist topsoil, but wet loads can weigh more. Screened topsoil spreads more evenly than rough, rocky fill.
Check that your truck or trailer can carry the weight shown. A single cubic yard of damp soil can top a ton.
Soil settles after you spread it, so order a little extra for deep fills. For a mulch layer on top of the soil, the mulch bag calculator sizes that. To frame the bed itself, use the garden bed calculator.
For a richer mix, the compost calculator and the garden soil calculator cover amendments. To size the yard first, the lawn area calculator helps. See more garden tools in the home and construction calculators hub.
Limitations and Assumptions
- The tool sizes one rectangular area. Break odd shapes into rectangles and add the volumes.
- The weight uses a single density of 1.07 tons per cubic yard. Your soil may be lighter or heavier.
- The bag count assumes 0.75 cubic foot bags, which many brands use. Other sizes vary.
- The bag count is based on a 0.75 cubic foot volume, not weight. A moist bag of that size weighs roughly 55 to 60 pounds.
- It adds no settling or waste allowance, so order a bit more for deep fills.
- A blank or out-of-range length, width, or depth shows an alert and sets each result to N/A.
FAQs About the Topsoil Calculator
How many cubic yards of topsoil do I need?
Multiply length by width by depth in feet, then divide by 27. For a 30 by 15 area at 4 inches, that is 5.56 yards.
How much does a cubic yard of topsoil weigh?
The tool uses about 1.07 tons, or roughly 2,140 pounds, for moist soil. Wet soil can weigh more.
How deep should topsoil be for a new lawn?
Many lawns use 4 to 6 inches of good soil. Deeper beds help roots and drainage.
How big is a bag of topsoil?
This tool assumes 0.75 cubic foot bags. It takes 36 such bags to equal one cubic yard.
Should I buy bags or bulk soil?
Bags suit small beds. Bulk by the cubic yard is usually cheaper once you need a yard or more.
Does the tool add extra for settling?
No. It gives the exact volume. Order a little more if the fill is deep or the ground is soft.
This calculator gives planning estimates only and is not professional engineering, electrical, or building code advice. Reviewed for general accuracy by Prof. Dr. Khalil Mudassar, PhD.