Topsoil Calculator

The Topsoil Calculator computes topsoil from the relation cubic yards = length ft x width ft x depth in / 324. It takes 3 inputs (length in ft, width in ft, depth in in) and returns the topsoil. Because this is a pure mathematical or physical formula rather than a jurisdiction-specific rule, the result never changes over time: the same inputs always produce the same answer, so you can rely on it whether you are checking homework, sizing a design, or sanity-checking another tool. Enter your values in the fields below and the result updates instantly; you can also share a permalink that pre-fills the exact calculation, which is useful for teaching, reports, or collaboration. For example, with length = 15 ft, width = 12 ft, depth = 4 in, the topsoil works out to 2.222222, and the worked example further down the page shows every step so you can follow the arithmetic and reproduce it by hand. The method is the standard form documented by CalculatorHub methodology, and the figure above each result carries the date it was last verified. This tool is general information and is not a substitute for professional engineering, medical, financial, or scientific advice; always check critical results against the primary source and your own judgement.

With Length = 15 ft, Width = 12 ft, Depth = 4 in, the result is 2.222222.

Formula: cubic yards = length ft x width ft x depth in / 324. Source: CalculatorHub methodology, as at 2026-06-23.

Topsoil2.222222

Applies to: any numeric inputs. Method source: CalculatorHub methodology, checked 2026-06-23.

The formula

cubic yards = length ft x width ft x depth in / 324

Worked example

With Length = 15 ft, Width = 12 ft, Depth = 4 in:

  1. area = 15 ft x 12 ft = 180 sq ft
  2. volume = area x 4 in / 324 = 2.2222 cubic yards
  3. Topsoil = 2.222222

This worked example is one of the automated golden-value tests this calculator must pass before it can publish.

What this assumes

  • Inputs are real numbers in the units shown.
  • The result is the exact value of cubic yards = length ft x width ft x depth in / 324; general information, not professional advice.

Frequently asked questions

What formula does this use?

cubic yards = length ft x width ft x depth in / 324, the standard form documented by CalculatorHub methodology.

Does the result ever change over time?

No. This is a pure formula with no external rate, so the same inputs always give the same result.

Official sources and verification

Reviewed by the CalculatorHub team, edited by James Graham, 2026-06-23. See our methodology. General information, not professional advice.