Bulk Landscape Material Calculator (Gravel / Topsoil / Mulch)

Estimate the volume, weight, or bag count for a measured covering or backfill area.

Inputs

Preset: 4x30 ft gravel path

A 4 by 30 ft path at 3 in depth. Weight mode assumes loose gravel at 100 lb/ft³; bags hold 0.5 ft³. No volume loss is assumed. Confirm density and any compaction factor with your supplier.

Project area

Application depth

Formula, inputs and conditions

Formula: Project area*Application depth/12/27

Decimal results are displayed to two places when needed.

Inputs: Area, application depth, material density in a matching state, and bag volume; the user or supplier provides any state-conversion factor.
Outputs: Cubic feet, cubic yards, U.S. short tons, and whole bags.
Conditions and scope: Distinguish loose, in-place, and compacted material. If a stated volume-loss rate s applies, purchase volume is target volume / (1 - s); do not add s directly. Use product-specific density and application depth for the material you intend to order. Results are planning estimates, not engineering, permit, code or contractor-price decisions.

Area, depth and the material you order

A square foot measures a surface; a cubic yard measures a volume. Gravel, topsoil and mulch estimates start by giving that surface a depth. Weight and bag counts are separate conversions, so a volume alone cannot tell you the number of tons to order.

Measure and calculate

Measure the area you will actually cover, subtracting openings and existing features.
Enter the intended depth and choose volume, weight or bags. Keep density in the same loose or compacted state as the volume.
Use the supplier’s bag size or material density before turning the estimate into an order.

Calculation method

Cubic yards = area in square feet × depth in inches ÷ 12 ÷ 27.

A worked example

Inputs: A 4 by 30 ft path covers 120 ft². The example fill depth is 3 in.
Calculation: 120 × 3 ÷ 12 = 30 ft³; 30 ÷ 27 = 1.1111 yd³.
Result: 1.11 yd³

The initial result is 1.11 yd³. At the example density of 100 lb/ft³, that same 30 ft³ weighs 3,000 lb, or 1.5 US short tons. Density and installation allowances must be checked separately.

Read the result

Output interpretation and next steps
Output or check	What it means for your project
Volume: ft³ or yd³	Volume describes space to fill. Keep the material state consistent; 27 ft³ equals 1 yd³.
Weight: US short tons	Use a matching density in lb/ft³. A short ton is 2,000 lb; volume alone does not determine weight.
Bags and loose volume	Bag count rounds upward to whole bags. The loose-volume mode divides the target by the retained fraction; do not apply that conversion twice.

Common questions

Is one cubic yard always the same weight?

No. A cubic yard is a volume. Material type, moisture and packing affect weight; use a density matching the material you will receive.

Should I add a loss percentage directly?

If a stated fraction of delivered volume is lost, divide the target volume by one minus that fraction. A 20% loss requires division by 0.8, not multiplication by 1.2.