Calculators
Rectangular Bipyramid Calculator
Calculate centered rectangular bipyramid volume, exterior surface area, and four face slant heights from base dimensions and two heights.
Measure two pyramids joined at a rectangular base.
Both tips lie on the perpendicular line through the shared rectangle center, on opposite sides. Enter base length a, width b, and perpendicular heights h₁ and h₂ in the same unit. Internal base area B = ab; volume V = ab(h₁ + h₂)/3. For each height h, faces attached to length-a edges have slant height hypot(h, b/2), while faces attached to width-b edges have slant height hypot(h, a/2). Exterior area is a times the sum of the two length-edge slant heights plus b times the sum of the two width-edge slant heights. The internal rectangle is excluded. For a = 6, b = 8, and both heights = 3, volume is 96 cubic units and exterior area is approximately 127.882250994 square units. Equal base dimensions give a square bipyramid. Unequal heights are supported; off-center tips require other surface formulas. Use positive lengths from 1e-50 to 1e50; scientific notation is accepted. Results use browser floating-point arithmetic rounded to 12 significant digits. All inputs stay in your browser.
Frequently Asked Questions
Everything you need to know about this tool, how it works, and privacy.
Where must the tips lie?
Directly above and below the center of the shared rectangle, on opposite sides. Heights are perpendicular distances from the base plane.
Does exterior area include the rectangle?
No. The shared rectangle is internal. Exterior area includes only the eight triangular faces.
Why are there four slant heights?
A rectangular pyramid has two pairs of faces with different base-to-center distances. Each pyramid contributes two slant heights; some coincide for square bases or equal pyramid heights.
Do I need matching units?
Yes. Use the same length unit for all inputs. Volume is in cubic units and area in square units. Inputs and calculations stay in your browser.