Potting Soil Calculator
Rectangular planter interior volume.
Step 1: Units
Step 2
Enter project measurements
Use decimals if needed (e.g. 3.5).
Step 3
How to use this calculator
Inside dimensions of the container.
What the math is doing
Volume = length × width × depth.
Frequently asked questions
Perlite mix?
Buy blended bags for specialty mixes.
Drainage layer?
Add coarse layer volume separately.
Large pots?
Consider soilless media weight.
Saucers?
Overflow planning.