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Raised Bed Soil Calculator

Add one or more raised beds to get the total soil volume, bag count and a topsoil / compost / aeration mix breakdown.

Written by Jude Ramsey · Last updated August 2026 · How these calculators are checked

How raised bed soil is worked out

Filling a raised bed takes more soil than people expect. This raised bed soil calculator adds up every bed you enter, returns the total in cubic feet and cubic yards, and breaks it into a recommended soil mix so you know how much of each ingredient to buy.

Choose a standard blend, a Mel’s Mix, or a veg-rich mix, and the calculator splits the total volume accordingly.

The default scenario, worked through

As an example, with a bag size of 1.5 ft³ bag, soil mix of Standard — 50% topsoil · 30% compost · 20% aeration, the calculator returns a raised bed soil of 6.67. Underneath, Total cubic feet comes out at 6.67 and Total cubic yards at 0.247. Change any field and every figure updates as you type.

Step by step

  1. Set your length/width units and depth units, then enter each bed’s size.
  2. Add more beds with the button if you have several.
  3. Pick a soil mix and read the total volume, bags and the mix breakdown.

The formula

per bed (ft³) = length × width × depth total cubic yards = total ft³ ÷ 27 bags = total ft³ ÷ bag size

Common questions

What’s the best raised bed soil mix?
A reliable blend is about 50% topsoil, 30% compost and 20% aeration such as coarse sand or bark. “Mel’s Mix” uses equal parts compost, peat/coir and vermiculite.
How deep should a raised bed be?
6 inches works for greens and herbs; 10–12 inches is better for roots, tomatoes and most vegetables.
Can I fill the bottom to save soil?
For deep beds you can part-fill the base with sticks and leaves (a hügelkultur base), then top with your soil mix.

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