Mulch, Soil & Gravel Calculator

What does this calculator do?

The Mulch, Soil & Gravel Calculator turns a rectangular area and a depth into what you actually need to buy: volume, estimated weight, how many bags, and how many truck loads — for mulch, topsoil, gravel, or sand. It covers the whole shopping-list question in one pass instead of separate area, volume, and bag-count calculations, and every result is shown in both imperial and metric so it doesn't matter which system you shop in.

How the numbers are worked out:

1. Coverage area: length × width.
2. Volume: area × depth ÷ 12 (depth is converted to feet internally), given in both cubic yards and cubic meters.
3. A waste/overage percentage is added on top — compaction, spillage, and uneven ground mean you almost always need a bit more than the bare math.
4. Weight: volume with waste × material density. Density is a commonly-cited landscaping-supply average per material — mulch ≈ 500 lb/yd³, topsoil ≈ 2,000 lb/yd³ (roughly 1 ton), gravel ≈ 2,800 lb/yd³, sand ≈ 2,700 lb/yd³. Real density varies with moisture and grade, so treat this as a solid estimate, not a scale reading.
5. Bags needed: volume with waste ÷ your bag size, rounded up — you can't buy a fraction of a bag.
6. Truck loads: volume with waste ÷ your truck's capacity, rounded up to the number of trips required.

Worked example: a 10×20 ft mulch bed at 3 inches deep needs 200 × 0.25 = 50 ft³ (1.85 yd³) of mulch. With 10% waste that's 2.04 yd³ (1.56 m³), about 1,019 lbs (462 kg), 28 bags at 2 ft³ each, and 2 truck trips at 2 yd³ per load.

How to use it

1. Pick the material — mulch, topsoil, gravel, or sand.
2. Pick a unit system — imperial (feet, inches, cubic feet, cubic yards) or metric (meters, centimeters, liters, cubic meters). This one toggle sets the unit every field below is entered in, so there's no more guessing which field wants feet versus meters.
3. Enter the length and width of the area.
4. Enter the depth — inches in imperial (3" is typical for mulch, 4-6" for gravel driveways, 2-4" for topsoil beds), centimeters in metric.
5. Set a waste percentage to buy a bit of buffer — 10% is a reasonable default.
6. Enter your supplier's bag size and your vehicle's truck/trailer capacity — both are editable rather than hidden assumptions, since actual bag sizes and hauling capacity vary a lot by supplier and vehicle (and by unit system: 2 ft³ is a common imperial bag, 50 L a common metric one).

The results table updates as you type, with every row showing both imperial and metric so you can read off whichever unit you actually buy in. Copy or download it as CSV.

Why are bag size and truck capacity fields instead of fixed values?

Bag sizes vary by supplier and material — 0.5, 1, 1.5, and 2 cubic feet are all common on store shelves — and truck/trailer capacity depends entirely on what you're hauling with. Making both editable means the bag and trip counts match what you're actually buying and driving, instead of a one-size-fits-all guess.

How accurate is the weight estimate?

Material density is the biggest source of variation here. Mulch density swings widely by type (shredded bark vs. wood chips vs. rubber) and moisture; topsoil and sand get noticeably heavier when wet. The figures used are reasonable planning averages, not a substitute for asking your supplier's published density if you need an exact weight (e.g. for a vehicle's load rating).

Privacy

This calculator runs entirely in your browser. Your measurements, material choice, and supplier details are never sent to a server, logged, or stored — the math happens locally on your device.