Cross Product Calculator
The cross product is a fundamental operation on 3D vectors that produces a new vector perpendicular to both input vectors. It is essential in physics, engineering, and computer graphics for calculating torques, surface normals, and angular momenta. This calculator computes the cross product A × B and its magnitude, showing you the resulting perpendicular vector and how the vectors' orientations affect the result.
Cross product formula
A × B = (a2*b3 - a3*b2, a3*b1 - a1*b3, a1*b2 - a2*b1)
|A × B| = |A| * |B| * sin(θ)
Cross product calculator: frequently asked questions
What is the cross product?
The cross product of two 3D vectors A and B produces a third vector perpendicular to both. The formula is A × B = (a2*b3 - a3*b2, a3*b1 - a1*b3, a1*b2 - a2*b1). The magnitude of the cross product equals |A| * |B| * sin(θ), where θ is the angle between them.
How does the right-hand rule work?
The right-hand rule determines the direction of the cross product. Point your right hand's fingers in the direction of A, curl them toward B, and your thumb points in the direction of A × B. This is crucial because B × A points in the opposite direction.
What does it mean if the cross product is zero?
A zero cross product means the vectors are parallel (or one is zero). Parallel vectors are either in the same direction or opposite directions. Geometrically, they lie on the same line.
Why is cross product only defined in 3D?
The cross product produces a vector perpendicular to both input vectors. In 3D space, there is exactly one perpendicular direction (up to orientation). In 2D, perpendicularity doesn't work the same way. In higher dimensions, multiple perpendicular directions exist.
What are applications of the cross product?
Cross products are used in physics (torque = force × position), computer graphics (computing surface normals), engineering (angular momentum), and electromagnetism (Lorentz force). They are essential for 3D geometric calculations.
Official sources
- Khan Academy: Cross product.
- Wolfram MathWorld: Cross product.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.