How much topsoil do I need for a raised bed?
Use inside bed measurements, soil depth, and the product bag volume to plan a raised-bed fill.
Short answer
Measure the inside of every bed, multiply length by width by depth, add the beds together, and compare the volume with the bag or bulk unit you plan to buy.
For homeowners filling one or more raised beds with bagged or bulk soil.
How to do it
Measure inside the bed
Enter the inside length and width for each raised bed so the walls are not counted as soil.
Set the fill depth
Give each bed its own depth when the beds are different sizes or will be filled to different levels.
Choose the fill level
Use the fill percentage when you plan to leave space or top the bed up later.
Check the package
Enter the volume printed on the bag or compare the target with a bulk delivery quote.
Formula
Each bed's length multiplied by width and depth is totaled, then the selected fill percentage is applied.
Illustrative example
An 8 × 4 ft bed at 12 inches is 32 cu ft. Add a second 6 × 3 ft bed at 10 inches, and the combined volume becomes the starting point for bag planning.
Common mistakes
- Using outside bed dimensions
- Assuming every bed has the same depth
- Using bag weight instead of labeled volume
Before you buy
Use the bag volume printed on the product. For bulk soil, compare the target cubic-yard volume with the supplier's delivered unit.
What this guide does not cover
The estimate does not recommend a soil recipe, drainage layer, settling schedule, or crop-specific growing medium.
Use the calculator
Raised-Bed Soil Calculator is the primary tool for this guide. You can also browse the other landscaping calculators.