What is a cubic yard?
A cubic yard is a unit of volume equal to a cube that is 3 feet on each side. That makes it 27 cubic feet, or about 0.7646 cubic metres. Landscape suppliers, concrete plants and mulch yards sell bulk material by the cubic yard, so it is the number you need before you place an order.
Cubic yard formula
Convert every measurement to feet, multiply them to get cubic feet, then divide by 27.
cubic yards = (length × width × depth) ÷ 27
Step-by-step example
Say you want to spread 4 inches of mulch over a bed that is 10 ft long and 8 ft wide.
| Step | Calculation | Result |
|---|---|---|
| 1. Convert depth to feet | 4 in ÷ 12 | 0.333 ft |
| 2. Find cubic feet | 10 × 8 × 0.333 | 26.67 ft³ |
| 3. Convert to cubic yards | 26.67 ÷ 27 | 0.99 yd³ |
One cubic yard covers this bed. Add 5–10% on top if the ground is uneven.
How much does a cubic yard weigh?
Weight depends on the material. The calculator uses approximate densities: topsoil about 2,200 lb per cubic yard, mulch about 900 lb, gravel and sand about 2,800 lb and concrete about 4,000 lb. Moisture and particle size change these numbers, so treat the weight as an estimate and confirm with your supplier.
Common mistakes
- Mixing units, such as measuring length in feet but depth in inches without converting.
- Forgetting a waste allowance. Most projects need a little extra.
- Ordering by area. Suppliers sell by volume, so depth matters as much as area.
How to use this calculator
- Enter your values. Work out how many cubic yards of soil, mulch, gravel, sand or concrete your project needs.
- Check units and assumptions. Make sure the inputs use the same scale and that any optional settings match your situation.
- Calculate and review. Compare the output with the formula below and note any limitations stated on the page.
Formula and calculation method
For rectangular spaces, calculate length × width × depth after converting all measurements to the same unit. Convert cubic feet to cubic yards by dividing by 27. Add a waste allowance only when appropriate for the material and project.
Worked example
For example, a 10 ft × 8 ft area filled to 1 ft deep is 80 cubic feet. Dividing 80 by 27 gives about 2.96 cubic yards before any allowance for compaction, uneven ground, or waste.
Search and practical tips
People commonly search for a cubic yard calculator – free volume tool, how to calculate the result step by step, which formula to use, and how to check the answer manually. Use the formula above as a transparent starting point, and consult the relevant institution, agency, or qualified professional when an official rule or personal circumstances affect the result.
Frequently asked questions
How many cubic feet are in a cubic yard?
There are 27 cubic feet in one cubic yard, because a cubic yard is 3 feet long, 3 feet wide and 3 feet tall.
How do I calculate cubic yards from square feet?
Multiply the area in square feet by the depth in feet, then divide by 27. For 100 square feet at 3 inches deep: 100 × 0.25 ÷ 27 = 0.93 cubic yards.
How much extra material should I order?
Most projects need 5–10% extra to cover settling, uneven ground and spillage. Use the waste allowance field to add it automatically.
How many 80 lb bags of concrete make a cubic yard?
Roughly 45 bags. An 80 lb bag yields about 0.6 cubic feet, and 27 ÷ 0.6 = 45. Pick Concrete in the material list to see the estimate.
Can I use it for a round area?
The tool is built for rectangles. For a circle, find the area with π × radius², multiply by the depth in feet and divide by 27.