GravelMulchMath: free gravelmulchmath planning calculators

Every landscape order starts with one shape

Almost every bulk material question on a home project comes down to the same box: how long, how wide and how deep. A garden bed, a path, a parking pad and a sandbox all become a rectangle (or a few rectangles) with a thickness. Once you know the volume, everything else follows: how many bags fill it, how many yards to order, how much the load weighs and roughly what it might cost. This site exists to make that arithmetic quick and transparent, so you can walk into a landscape yard or call a supplier with a number you understand.

The calculators show their working. Each result lists cubic feet, cubic yards and cubic metres, and where it makes sense, an estimated weight in US tons and metric tonnes. Every assumption you would normally have to guess, such as density or extra allowance for compaction, sits in a field you can change. Defaults are illustrative starting points, not promises about any particular product.

Pick the right calculator

Use the gravel calculator for general stone, the driveway version when vehicles will use the surface, and the paver base tool when you need both a compacted base and a bedding layer. For soft materials, the mulch calculator returns bag counts as well as yards, and the bags vs bulk comparison tells you which way of buying is cheaper with your local prices. If a supplier quotes by weight, convert with cubic yards to tons.

Measuring without mistakes

Measure in feet where you can and write down each section separately. Irregular beds are easiest as several rectangles plus a triangle or two; add the areas before entering them. For a circle, area is 3.14 multiplied by the radius squared. Depth is the number people most often get wrong, because a guess of "a few inches" can double or halve an order. Push a ruler into the existing material in several places and average the readings. When you are topping up rather than starting fresh, enter only the difference between the current depth and the depth you want.

Remember that slopes are measured along the ground, not on a map. A path that climbs a bank is longer than its footprint on a satellite image. Edges matter too: if a bed is bordered by a raised edging, the material fills to the top of that edging, which may be deeper than you planned.

Volume versus weight

Bulk landscape materials are sold in two ways. Some yards sell by the cubic yard, a measure of space. Others sell by the ton, a measure of weight. Neither is better; they simply require a conversion. Stone is dense, so a yard of gravel might weigh around one and a half tons, while a yard of shredded bark weighs a small fraction of that. Moisture changes things too: sand and soil delivered wet weigh noticeably more than the same volume dry. That is why our calculators ask for density rather than hiding a single fixed number, and why the honest answer to "how many tons is a yard" is "ask your supplier for their measured figure".

Weight also matters for the trip home. A single cubic yard of stone can exceed the payload rating of many half-ton pickups and small trailers. Check the sticker on your door jamb or trailer tongue before you load, and consider delivery for anything over a yard or so.

What these numbers are, and are not

Every figure here is a geometry estimate. We do not know your soil, your drainage, your frost depth or how a driveway will be loaded, so we do not tell you what depth is structurally adequate. Where guides mention typical depths, they describe common practice to help you ask better questions, not a design. For anything that carries vehicles, changes how water leaves a building, or retains soil, talk to a local contractor or the relevant authority. Prices in our guides are labelled illustrative and dated so you can see how old they are.

Guides worth reading before you order

Start with gravel types if you are unsure which stone suits a job, and mulch types for beds. The project FAQ collects short answers to the questions people ask most often.

Metric quick reference

For readers measuring in metres, this table converts area and depth to cubic metres and an approximate tonne figure for stone at 1.4 US tons per yard.

A note on rounding up

Suppliers often load in half or whole yards, so a result of 2.3 yd³ usually becomes 2.5. Rounding up is cheaper than a second delivery, but a large surplus of stone is hard to store. Leftover mulch keeps for a season under a tarp; leftover gravel can top up paths later.

Worked example

Illustrative examples (2026-10-29), not quotes or guarantees.

A rear yard project has a 40 × 3 ft path (120 ft²) at 3 in of pea gravel and two beds totalling 180 ft² at 3 in of shredded mulch. Path: 30 ft³ ≈ 1.11 yd³ ≈ 1.56 tons at 1.4. Beds: 45 ft³ ≈ 1.67 yd³, about 23 bags of 2 ft³, or bulk with delivery. One supplier trip for stone, one for mulch.

FAQ

Is the calculator free?

Yes. No sign-up, no tracking cookies on this preview.

Do you sell gravel?

No. We do not sell materials or rank suppliers.

Are the densities exact?

No. They are editable defaults; your supplier's figure always wins.

Can I use metric?

Convert metres to feet (× 3.28); results include m³ and tonnes.

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