Calculateus

Landscape Edging Calculator

Calculate the linear feet of edging needed for a garden bed or lawn border.

Result

Edging Needed
46 ft (14 m)
Pieces Needed
6

About the Landscape Edging

Garden bed edging is priced by the linear foot, and a bed's true perimeter, whether rectangular or circular, is what determines how many pieces of edging material to buy.

How It Works

The calculator finds the bed's perimeter, either using standard rectangle math or a circle's circumference formula based on the entered diameter, then divides by the edging piece length to find how many pieces are needed.

rectangle: perimeter = 2 × (length + width); circle: perimeter = π × diameter

Examples

A rectangular border bed

A 15×8 ft rectangular bed has a 46 ft perimeter, needing about 6 pieces of 8 ft edging.

A circular tree ring

An 8 ft diameter circular bed has about a 25.1 ft circumference, needing about 4 pieces of 8 ft edging.

Advantages

  • Supports both rectangular and circular bed shapes with the correct formula for each
  • Converts perimeter directly into a purchasable piece count
  • Shows results in both feet and meters

Common Mistakes

  • Entering a circular bed's radius instead of its full diameter
  • Not accounting for extra material used by cuts at corners or along curves
  • Treating a freeform bed shape as a perfect rectangle or circle without adjustment

Edge Cases to Watch For

  • For a circular bed, the width field entered is treated as the full diameter, not the radius, since that's what most people measure directly across a round bed.
  • Curved or freeform bed shapes aren't directly supported; approximating them as a rectangle or circle, or breaking them into segments, gives the closest estimate.
  • Rigid edging pieces need to be cut at corners or along curves, which uses slightly more material than the raw perimeter figure alone.

Common Use Cases

  • Estimating edging material for a new garden bed border
  • Budgeting a landscape edging project for a circular tree ring or planting bed
  • Comparing material needs between rectangular and circular bed layouts
Written & fact-checked by the Calculateus TeamLast updated August 5, 2026How we verify our formulas

Frequently asked questions

For a circular bed, is "width" the radius or the diameter?

It's the diameter (the full width across the circle) - the calculator uses π × diameter to find the circumference, which is the total edging length needed to go all the way around.

Conclusion

Perimeter is the whole calculation here, whether from simple rectangle math or a circle's circumference, and getting the shape formula right matters more than any waste allowance. Round up to the next full piece and expect a bit of extra cutting at any corners or curves.