MeasureSparkConversions
Rectangular Volume Calculator
Use this for boxes, rooms, soil beds, storage spaces, and other rectangular volumes. Divide cubic feet by 27 for cubic yards.Enter your measurements
Volume = length × width × height.
How this estimate works
Volume = length × width × height.
Measure twice and use the same unit throughout. Product coverage, material density, installation patterns, and local requirements can change the quantity you need.
Quick answer
For a rectangular space, multiply length by width by height. When all three inputs are in feet, the result is cubic feet.
Worked example
An 8 × 4 × 2 ft rectangular space has a volume of 64 ft³. Dividing by 27 converts that volume to about 2.37 yd³.
Assumptions
- The object or space is a rectangular prism.
- All three dimensions use the same unit.
- The result is geometric volume without compaction, fill, or waste factors.
What does a cubic foot represent?
One cubic foot is the volume of a cube that measures one foot on every side. Volume has a cubed unit because three perpendicular lengths are multiplied.
How do I convert cubic feet to cubic yards?
One yard equals three feet, so one cubic yard contains 3 × 3 × 3, or 27, cubic feet. Divide cubic feet by 27 to get cubic yards.
When is this formula not appropriate?
Use a shape-specific formula for cylinders, cones, sloped containers, or irregular excavations. Material orders may also require density, compaction, settling, and waste allowances that are not part of simple geometric volume.
How do I go from box volume to mulch bags?
If the rectangle is a soil or mulch bed, convert cubic feet to yards here, then open the mulch calculator to apply depth, an 8% settling allowance, and 2 cu ft bag rounding. Do not treat geometric volume as a store quantity by itself.
Last reviewed September 22, 2026. Source: NIST SI unit guidance for volume. Product instructions take priority over a general estimate.
Common questions
Short answers for the measurement details people most often need before using this calculator.
How do I calculate the volume of a rectangular box?
Multiply length × width × height in the same unit. With feet, the result is cubic feet. Divide by 27 for cubic yards.
How much soil or mulch is that in cubic yards?
Convert the geometric cubic feet to yards, then use the mulch calculator if you also need bag count and a settling allowance. This page does not add waste or compaction.