How Much Mulch Do I Need? Cubic Yards and Bags by Bed Size

Q: How much mulch do I need?

Multiply the area by the depth to get a volume, then multiply by 250 kg per cubic metre to get the weight. At 3 inches deep, 100 square feet needs about 0.91 cubic yards, which weighs about 0.19 US tons.

How much mulch do I need?

Multiply the area by the depth for a volume, then multiply the volume by 250 kg per cubic metre for a weight. At 3 inches deep, 100 square feet of mulch is about 0.91 cubic yards, which weighs about 0.19 US tons. Enter your own measurements below.

Mulch calculator

Shape of the area

RectangleCircleL-shapeTriangle

Length

Width

Depth

Typical:

Extra for wasteMulch settles and breaks down, and bags are rarely filled to the brim. Ten percent is the usual allowance.

PriceYour supplier's price, so the total is yours and not an average.

Use your supplier's density

Bulk densityPublished figures for mulch run from 200 to 300 kg/m3, a spread of 50 percent. This calculator uses 250. If your supplier states their own figure, it beats any table.

kg/m3

This calculator needs JavaScript. The arithmetic is: area times depth gives volume, volume times bulk density gives weight, weight divided by your bag or load size gives what to order. For mulch, use 250 kg per cubic metre.

Enter your measurements to see what to order.

How much mulch for a given area

At 3 inches deep, the depth Mainland Aggregates recommends.

Area	Cubic yards	US tons	Cubic metres
100 sq ft	0.91	0.19	0.7
200 sq ft	1.82	0.38	1.39
400 sq ft	3.65	0.77	2.79
600 sq ft	5.47	1.15	4.18
1,000 sq ft	9.11	1.92	6.97

Every figure above is the calculator's own output at 250 kg per cubic metre, with no waste added. Add 10 percent to any of them before ordering.

Why two suppliers deliver different weights for the same order

Published densities for mulch run from 200 to 300 kg per cubic metre. On a 3.65 cubic yard order that is the difference between 0.61 and 0.92 US tons. Dry. Bark near 200 kg per cubic metre can roughly double after heavy rain, which puts a wet load above the top of this band.

3 published figures from 3 suppliers, read 2026-09-20.

Supplier	Published figure	Condition
Sky Nursery (Shoreline, WA)US	400-500 pounds per yard	unstated
Melcourt Industries LtdUK	Bulk Density 200 - 250 g/l	unstated (producer technical spec
Australian Native Landscapes (ANL)AU	Bark 0.3 (Tonnes / Metre)	loose ('Loose Tonnes' column)

How much extra to order

10 percent. Mulch settles and breaks down, and bags are rarely filled to the brim. Ten percent is the usual allowance.

How many tons in a cubic yard of mulch?

About 0.21 US tons, and one ton is about 4.75 cubic yards.

The mulch calculator handles circles, L-shapes and triangles, and switches to cubic metres and bulk bags.