Cubic Yard Calculator

Why Cubic Yards?

A cubic yard is 27 cubic feet — the volume of a 3 ft cube. Dump trucks and suppliers price bulk material this way, so estimating in yards lets you order correctly and compare delivery quotes.

What Affects Volume?

Volume is length × width × depth. Loose materials compact after delivery (soil can settle 10-20%), so a compaction allowance prevents shortfalls. Deeper projects (a raised bed vs a thin topdressing) scale linearly with depth.

Recommended depths by material

The formula is the same for every bulk material; only the depth changes. Topsoil for a new garden bed wants 4–6 in, lawn top-dressing 1–2 in, and a raised bed 8–12 in. Bark mulch goes 2–3 in for beds and 3–4 in for paths. Gravel for a driveway base needs 4–6 in, and decorative stone 2–3 in. Playground surfaces call for 6–12 in of certified wood fiber. Picking the right depth is the difference between a job that works and one that washes out.

Worked Example 1: A 20 ft × 10 ft Bed, 4 in Deep

Volume = 20 × 10 × (4/12) = 66.67 ft³. Yards = 66.67 / 27 = 2.47 yd³. With 10% → 2.72 yd³. Soil weighs about 1.35 ton/yd³, so ≈ 3.67 tons.

Worked Example 2: A 30 ft × 30 ft Pad, 6 in Deep

Volume = 30 × 30 × 0.5 = 450 ft³ = 16.67 yd³. With 10% → 18.33 yd³.

Edge Cases

• Zero dimension → no result.
• Deeper depth → more yards (linear in depth).
• Compaction → raises the order to offset settling.
• Non-rectangular → section and sum.
• Different materials → tons vary (gravel ~1.4, soil ~1.35, mulch ~0.4 ton/yd³).
• Wet material → heavier; ton estimates are dry approximations.

Worked Example 3: A Raised Bed 8 ft × 4 ft × 12 in

Volume = 8 × 4 × 1 = 32 ft³. Yards = 32 / 27 = 1.19, plus 10% → 1.30 yd³. A single yard is close, but the compaction margin pushes it to 1.5 yards to avoid a shortfall.

Worked Example 4: A 4 in Gravel Driveway 200 ft × 10 ft

Volume = 200 × 10 × (4/12) = 666.7 ft³ = 24.7 yd³. With 10% → 27.1 yd³. At ~1.4 ton/yd³ that is about 38 tons — well beyond a pickup, so order a dump truck.

Converting to bags

A cubic yard is 27 ft³. If you buy 2 ft³ bags of mulch, that is 13.5 bags per yard. Under about 2 yards, bags are easier; beyond that, bulk wins on price even after delivery.

Worked Example 5: A 50 ft × 20 ft Lawn Top-Dressing

A 1 in top-dressing over 1,000 ft² is 1,000 × (1/12) = 83.3 ft³ = 3.09 yd³. With 10% → 3.40 yd³. At ~1.35 ton/yd³ that is about 4.6 tons of screened topsoil spread thin across the whole lawn.

Worked Example 6: A 15 ft × 15 ft Raised Bed at 10 in

Area = 225 ft², depth 10 in: 225 × (10/12) = 187.5 ft³ = 6.94 yd³. With 15% (raised beds settle more) → 7.98 yd³. That is nearly eight yards of blended garden soil — a full dump truck, not bags.

Worked Example 7: A 12 ft × 16 ft Vegetable Garden at 8 in

A productive vegetable bed wants 8 in of amended topsoil so roots can reach. Area = 192 ft², depth 8 in: 192 × (8/12) = 128 ft³ = 4.74 yd³. With 12% compaction → 5.31 yd³. Because you will be mixing in compost on top of this, order the bulk soil a touch light and top-dress with bagged compost rather than paying for a full extra yard of blended material.

Worked Example 8: A 40 ft × 4 ft Side-Yard Path at 3 in

A narrow decomposed-granite or gravel path is long but shallow. Area = 160 ft², depth 3 in: 160 × (3/12) = 40 ft³ = 1.48 yd³. With 10% → 1.63 yd³. This is small enough that two or three 2 ft³ bags would do, but a supplier's 3-yard minimum usually makes bulk the only option, so combine it with another bed on the same order to clear the minimum charge.

Worked Example 9: Comparing depth choices on the same footprint

Take a 300 ft² area. At 2 in deep it is 300 × (2/12) = 50 ft³ = 1.85 yd³ + 10% = 2.04 yd³. At 6 in deep it is 150 ft³ = 5.56 yd³ + 10% = 6.11 yd³. Tripling the depth triples the yards, which is why picking the right depth from the start is the single biggest lever on your order and your delivery cost.

Depth rules of thumb by project

Sidewalk base gravel: 4–6 in. Paver base: 4–6 in. Garden bed soil: 6–12 in. Lawn top-dressing: 1–2 in. Playground wood fiber: 6–12 in. Driveway crush-run: 6–8 in for light use, more for vehicles. Pick the depth from this list, then let the calculator convert it to yards so you are not guessing.

Tonnage for delivery planning

A 10 yd³ topsoil order is about 13.5 tons; the same volume of gravel is 14 tons; the same of sand 15 tons. Most half-ton pickups carry under 1.5 tons legally, so anything past ~1 yard of heavy material needs a trailer or a dump truck. The ton figure from the calculator is what you give the supplier and the scale.

Circle and triangle areas

For a circular bed of radius r, area = π r². A 10 ft radius bed (314 ft²) at 4 in is 314 × (4/12) = 104.7 ft³ = 3.88 yd³ + 10% = 4.26 yd³. For a triangle, 0.5 × base × height. These feed the same depth-and-divide-by-27 formula; only the area step changes.

How many cubic feet in a yard?

27 cubic feet equal 1 cubic yard (a 3 ft × 3 ft × 3 ft cube).

How do I calculate cubic yards?

Multiply length × width × depth (in feet, with depth in inches divided by 12), then divide by 27.

How much does a yard of soil weigh?

About 1.35 tons for topsoil; gravel is heavier at ~1.4 tons.

Should I add compaction?

Yes, loose materials settle 10-20%; add that margin to avoid shortfalls.

How many yards in a dump truck?

Typically 10-14 cubic yards for a standard truck.

Does depth affect yards linearly?

Yes, doubling the depth doubles the volume and the yards.

Can I use this for mulch?

Yes, but mulch is much lighter (about 0.4 ton/yd³).

What if my area is not rectangular?

Break it into rectangles, compute each, and add the yards.

How much extra should I order?

Add 10% for compaction plus a little for spreading loss.

Is this the same as a gravel calculator?

The volume math is the same; only the material density for tons differs.

How many bags equal a yard?

A 2 ft³ bag takes 13.5 bags to make 27 ft³. Use bags under about 2 yards and bulk above that.

What depth should my mulch be?

Two to three inches for beds; more than four can smother plant stems and trap moisture. Paths and playgrounds go deeper.

Do I compact before or after calculating?

Calculate the loose volume, then add the compaction percentage in the calculator. Spreading and rolling settles the pile, so the "as delivered" number should already include the margin.

Can I estimate a circle or triangle?

Yes — use area = π r² for a circle or 0.5 × base × height for a triangle, then multiply by depth and divide by 27, same as a rectangle.

How do I avoid a short load fee?

Many suppliers have a minimum (often 3–5 yards) and charge for small deliveries. Batch several beds into one order to clear the minimum and share the delivery fee.

How wet is too wet to spread?

Wet material is heavier and compacts more, so a "yard" delivered in the rain may settle to less than a yard once it dries and packs. If you order in wet weather, the 10–15% margin matters more; dry, loose material matches the calculator's loose-volume assumption best.

What is the difference between screened and unscreened material?

Screened topsoil and gravel are sifted to a size, so they spread evenly and compact predictably. Unscreened "fill" may have clods and rocks that inflate the loose volume. The calculator assumes a workable, screened product; for rough fill, add a little extra.

Can I estimate a sloped or terraced yard?

Break a slope into horizontal bands by depth — the top of the slope gets less material than the bottom. Estimate each band as its own rectangle at its own depth, then sum. A single average depth underestimates a steep grade.

How do I convert yards to wheelbarrow loads?

A typical wheelbarrow holds 2–3 ft³. A cubic yard (27 ft³) is roughly 9–14 wheelbarrow loads. For an 8 yd³ order that is 70–110 trips — a good reason to order bulk delivery rather than bag-and-barrow small amounts.

Does mulch break down and need topping up?

Yes. Organic mulch decomposes, so beds that got 3 in this year may need 1–2 in refresh next year. The calculator gives the first fill; plan a lighter annual top-up using the same depth-and-area math at a smaller depth.

How many cubic yards for a new lawn?

A freshly graded lot seeded or sodded usually wants 4–6 in of topsoil before planting. A 1,000 ft² lawn at 4 in is 1,000 × (4/12) = 333 ft³ = 12.3 yd³ + 10% = 13.6 yd³. Sod itself is sold by the pallet (about 450 ft² per pallet), so estimate the soil separately from the sod; the volume math does not change, only the depth and material density inputs do.

Can I estimate a horseshoe or L-shaped bed?

Yes. Split the plan into rectangles: an L is one long leg and one short leg. Estimate each rectangle's yards at its own depth, then add them. Trying to average the whole shape into one rectangle usually under-counts the thicker leg, so keep the pieces separate and sum at the end for an accurate delivery number.

How much does delivery usually cost versus the material?

Bulk topsoil or gravel often runs $20–$45 per yard delivered in many markets, while the delivery truck itself may carry a flat $50–$100 trip charge plus a short-load fee under a few yards. That is why combining several beds into one minimum-clearing order beats several tiny separate drops; the calculator's yards tell you when you have crossed the economical bulk threshold.

Should I order the exact calculated yards?

Order the calculated yards rounded up to the next half or whole yard, then add a small buffer if the ground is uneven or you plan to build the beds slightly proud. Suppliers rarely refund a quarter yard, and a thin shortfall mid-job costs more in a second trip than a little excess you spread on a spare bed or border.

What if my supplier sells by the half-yard only?

Take the calculator's yard figure, round up to the nearest half. A result of 7.98 yd³ becomes 8 full yards; a result of 6.11 yd³ becomes 6.5 yards. Because the calculator already includes the compaction margin, this rounding is the only extra buffer you need for a typical loose-delivery job.