The Tapered Rectangular Planter Volume calculator computes the volume of a tapered rectangular planter based on the top and bottom side lengths and (h) height of the interior of the box (see diagram).
INSTRUCTIONS: Choose units and enter the following:
- (t) Top diameter of the circular planter
- (b) Base diameter of the circular planter
- (h) Height of planter or desired height of soil in the planter
Volume (V): The calculator returns the volume in cubic feet. However, this can be automatically converted into other volume units via the pull-down menu next to the answer. The calculator also returns the number of soil bags of the following sizes:
- 1 ft3
- 1.25 ft3
- 2.5 ft3
- 8 quarts
- 32 quarts
- 64 quarts
IMPORTANT NOTE: To compute the amount of soil needed in the planter, use the interior dimensions of the container, and use the top diameter associated with how high you want to fill the container. If you wish to fill to the brim, it is the full inner height.
The Math / Science
The Tapered Rectangular Planter Volume calculator computes the volume of a tapered rectangular planter. Enter the measurements of the planter: (t) top side length, (b) bottom side length and (h) height of the interior of the box (see diagram), then this formula will provide the volume of the container. Tapered Rectangular This answers the following questions:
- How much soil will my box planter hold?
- How much water will my box container hold?
- How much potting soil do I need?
If you do not intend to fill the container to the top, this formula will over estimate unless you use a height (h) that matches your expected top surface inside the container. Unless it's a very large container, and/or you are only using a small portion of the container, the overage should be small.
The Garden Soil Price Survey information is as follows:
- Date: 6/11/21
- Store: Multiple Sources
- Garden Soil (1 ft3): $5.99
- Garden Soil (1.5 ft3): $6.49
- Garden Soil (2 ft3): $8.49
- Potting Mix (1.25 ft3): $8.74
- Potting Mix (2.5 ft3): $12.36
The Pricing Data can be used the the Raised Planter calculator.
- Box (rectangular) Shaped Planter Volume
- Circular Shaped Planter Volume
- Polygon Shaped Planter Volume
- Triangular Shaped Planter Volume
- Tapered Rectangular Shaped Planter Volume
- Hexagon Shaped Planter Volume
- Octagon Shaped Planter Volume
Or just use the single calculator with all of the shapes available in one place at Planter Calculator. This includes some useful industry data like potting soil pricing from national advertisers.
The Math
This formula is based on the volume of a cuboid in 3-D geometry.