Landscape area take-off — rectangle, circle, triangle, and ring-bed formulas summed per section
A bed rarely is a clean rectangle. Add one section per shape and the calculator sums the areas: rectangle = L × W, circle = π(D/2)², triangle = ½ × B × H, and a ring around a tree = π(R² − r²) — remember to subtract the trunk gap. Total area × depth = the volume you order.
What this diagram shows
Four small diagrams showing how to get the square footage of any landscape section, because the calculator takes one section per shape and adds the areas. A rectangle uses area equals length times width, shown as 12 feet by 8 feet equals 96 square feet. A circle uses area equals pi times the radius squared, shown as a 10-foot diameter bed equals 78.5 square feet. A triangle uses area equals one half base times height, shown as a 10-foot base and 6-foot height equals 30 square feet. A ring or annulus, the bed around a tree, uses area equals pi times the outer radius squared minus the inner radius squared, shown as a 4-foot outer radius with a 1.5-foot trunk gap equals 43 square feet — the shape people forget to subtract the middle from. Each section area is summed, then multiplied by depth to get the volume ordered.
Use this diagram — free
You're welcome to use this diagram on your own site, blog, handout, or lesson at no cost. The only condition is a visible credit link back to the source page. Copy the snippet below and paste it into your page — the credit is already included.
Please keep the credit link intact and don't alter the diagram itself. Redistribution as part of a competing diagram library or template pack isn't permitted. Questions? Reach us via the site.
Was this diagram helpful?
Landscape Material Calculator
Calculate cubic yards, tons & bags for gravel, crushed stone, sand, river rock, topsoil, and riprap. ASTM D448 / AASHTO M43 gradations. Free.
