Latus Rectum Calculator

Latus Rectum Calculator

Calculate the latus rectum length for a parabola, ellipse, or hyperbola.

Last updated: June 2026 | By Patchworkr Team

Main Calculator

Latus Rectum Length
16
4a

Formula

Parabola: 4a
Ellipse/Hyperbola: 2b^2 / a

Use the parabola form when only a is needed; ellipses and hyperbolas use both a and b.

How to Use This Calculator

  1. Choose the conic type.
  2. Enter the required axis values.
  3. Read the latus rectum length in the result panel.

Worked Example

Ellipse with a = 5 and b = 4
length = 2 * 4^2 / 5 = 6.4

Frequently Asked Questions

Why does the formula change by conic?

The standard parabola definition differs from the ellipse and hyperbola forms used here.

Can the result be negative?

No. The calculator rejects invalid parameters instead of returning a negative length.

Does the tool accept decimals?

Yes. Any finite real value is accepted, including decimal and scientific notation inputs.

Why is b hidden for parabolas?

The parabola formula only depends on a, so b is not needed in that mode.

Related Tools