Cubic Yard Calculator
Measurements in, cubic yards out. Any shape, any units, several areas at once — with the waste allowance applied and every step of the arithmetic on show.
Measure
Enter the dimensions. Add more areas if the job has several — they add up into one total.
Appears on the printed and copied results.
Length × width × depth. The usual case.
Identical copies of this area.
Waste allowance
Added on top of the measured volume. Set it to 0% if you only want the conversion.
The formula
There is only one, and it is worth knowing by heart:
length (ft) × width (ft) × depth (ft) ÷ 27 = cubic yards
The single place this goes wrong is depth. Material depth is quoted in inches and the formula wants feet, so 4 inches has to become 0.333 ft before it is multiplied. Type 4 instead and the answer comes out twelve times too big — which is the mistake behind most over-ordered driveways.
Worked through: a patio 12 ft × 10 ft at 4 inches deep is 120 ft² × 0.333 ft = 40 ft³, and 40 ÷ 27 = 1.48 cubic yards. Add 10% for waste and you order 1.63.
Why 27?
A cubic yard is a cube one yard on each side. A yard is three feet, so the cube is 3 ft × 3 ft × 3 ft — twenty-seven cubic feet. It is a definition, not a measurement, so the conversion is exact: no range, no source, no tolerance. The only part of a material order that genuinely varies is the weight of that volume, which is a property of the material rather than of the arithmetic.
Square feet to cubic yards, by depth
The table most people actually want. Multiply your square footage by the figure in the right-hand column, or read across from the coverage column to see how far a single yard goes.
| Depth | yd³ per 100 ft² | ft² per yd³ | yd³ per ft² |
|---|---|---|---|
| 1″ | 0.31 | 324 ft² | 0.0031 |
| 2″ | 0.62 | 162 ft² | 0.0062 |
| 3″ | 0.93 | 108 ft² | 0.0093 |
| 4″ | 1.23 | 81 ft² | 0.0123 |
| 5″ | 1.54 | 65 ft² | 0.0154 |
| 6″ | 1.85 | 54 ft² | 0.0185 |
| 8″ | 2.47 | 41 ft² | 0.0247 |
| 12″ | 3.70 | 27 ft² | 0.0370 |
The 4-inch row is the one worth remembering: one cubic yard covers 81 square feet, so square footage ÷ 81 gives the yards.
Conversions
| 1 cubic yard equals | Amount |
|---|---|
| Cubic feet | 27 ft³ |
| Cubic inches | 46,656 in³ |
| Cubic metres | 0.7646 m³ |
| US gallons | 201.97 gal |
| Litres | 764.6 L |
| 2 ft³ bags | 13.5 bags |
| 1.5 ft³ bags | 18 bags |
The metric figures follow from the international yard, defined as exactly 0.9144 metres since 1959. Everything else here is exact arithmetic.
Waste allowances
| Site | Allowance | When |
|---|---|---|
| None | 0% | You are converting a known figure, not ordering material. |
| Tidy site | 5% | Flat, formed, well-prepared — little spillage. |
| Typical | 10% | The usual allowance for an ordinary job. |
| Rough ground | 15% | Uneven subgrade, hand spreading, awkward access. |
Trade practice rather than a standard. The allowance covers spillage, spreading loss and a subgrade that is never quite as flat as the tape suggests.
Measuring awkward shapes
- Circles — measure the diameter across the widest point, not the radius. Halving it is the calculator's job and a frequent source of a four-times error when done by hand.
- Tapers — a drive that widens from 9 ft to 14 ft is a trapezoid. Average the two widths and multiply by the length; the taper option does it.
- Irregular outlines — cut them into rectangles and triangles you can measure, and add each as its own area.
- Varying depth — measure the depth in several places and use the average. A slope from 2 in to 6 in behaves as a uniform 4 in.
- Already have the square footage? Use the "known square footage" option and just add a depth.
When to use a material calculator instead
Cubic yards are the universal language of material ordering, but they are not always what the supplier sells in. Once you know what the material is, the specific calculator will take the volume further:
- Ordering concrete? Use the Concrete Calculator — it rounds to the quarter yard a plant can batch, counts bags and truckloads, and flags a possible short-load charge.
- Ordering gravel or crushed stone? Use the Gravel Calculator — quarries sell by the ton, and dense-graded material has to be ordered loose to reach a compacted depth.
This page deliberately stops at volume. Applying a density, a compaction factor or a bag yield without knowing the material would be a guess dressed up as a calculation.
Frequently asked questions
How do I calculate cubic yards?
Measure length, width and depth in feet, multiply the three together for cubic feet, then divide by 27. The divide-by-27 step is where depth in inches usually goes wrong: 4 inches is 0.333 feet, not 4. The calculator above converts each field from whatever unit you entered it in, so you can type the depth in inches and the length in feet without doing any conversion yourself.
Why do you divide by 27?
A cubic yard is a cube one yard on each side, and a yard is 3 feet. So it holds 3 × 3 × 3 = 27 cubic feet. That is a definition rather than a measurement, which is why the conversion is exact and never needs a source or a tolerance.
How do I convert square feet to cubic yards?
Square footage alone is not a volume — you also need a depth. Multiply the area in square feet by the depth in feet, then divide by 27. A shortcut worth memorising: at 4 inches deep, one cubic yard covers 81 square feet, so dividing your square footage by 81 gives the yards. The "known square footage" option above does this for you.
How many cubic feet are in a cubic yard?
Exactly 27. There are also 46,656 cubic inches, about 202 US gallons, and about 0.7646 cubic metres.
How much does a cubic yard weigh?
That depends entirely on the material, which is why this calculator does not guess. Broadly: gravel and crushed stone run about 1.2 to 1.6 tons, topsoil about 1.0 to 1.3, wet sand more, and bark mulch only about 0.4. Concrete is much heavier at roughly 2 tons. If you need weight or tonnage, use the material calculator — it carries sourced density ranges instead of a single invented figure.
How many cubic yards fit in a pickup truck?
A full-size pickup bed holds roughly 2 to 2.5 cubic yards level with the rails. Weight is usually the real limit rather than volume: 2 yards of gravel is about 3 tons, which is well over what a half-ton truck should carry, while 2 yards of mulch is only a few hundred pounds. Check the payload rating, not just the bed size.
Can I add up several areas?
Yes. Add an area for each part of the job — a patio, a path, two planting beds — and each keeps its own shape, dimensions and depth. The total, the waste and the order quantity cover all of them together, and the per-area breakdown shows where each figure came from.
How much waste should I add?
Five to ten per cent is the usual allowance, and ten is a reasonable default for material going onto open ground. Tidy, formed work can take five; rough subgrade, hand spreading or awkward access justify fifteen. If you are only converting a known figure rather than ordering, set it to zero.
What about an irregular shape?
Split it into rectangles, triangles and circles you can measure, and add each as its own area. The trapezoid option handles anything that tapers along its length, such as a widening driveway. For a genuinely awkward outline, measure the square footage by whatever means you have and use the "known square footage" option.
Is a cubic yard the same as a yard of material?
In ordinary supplier conversation, yes — when a yard quotes you "three yards of mulch" they mean three cubic yards. It is worth confirming on a first order, because the same word is also a length.
Sources
Every figure on this page is exact arithmetic from the definition of the unit: a yard is three feet, so a cubic yard is 27 cubic feet, and the international yard has been defined as exactly 0.9144 metres since 1959. Nothing here rests on a measured or estimated constant, so nothing here needs one. Where a real material constant is required — density, compaction, bag yield — it lives in the material-specific calculators, each with its citation on the methodology page.
Last reviewed September 16, 2026.
Related
- Concrete Calculator — slabs, footings, post holes and more, consolidated into one pour.
- Gravel Calculator — layered areas, sourced density ranges and the loose tonnage to order.