Math calculators

Cross Product Calculator

Updated Jul 2, 2026 By Jehan Wadia
Vector Input
Input Method
Dimension
Vector A
Vector B
Quick Presets
Example Problems
Output Options
places

Cross Product Result
Component form
i, j, k notation
Vector Operations
Magnitude |A × B|
Parallelogram area
Triangle area
Angle θ between A and B
Unit normal n̂
Dot product A · B
Related Calculations
Reversed cross product B × A
Anti-commutative property
Step-by-Step Solution
Right-Hand Rule
Component Comparison
3D Vector Diagram
Check Your Answer

Introduction

The cross product calculator helps you find the cross product of two vectors in seconds. The cross product is a math operation that takes two vectors and gives you a new vector that points straight up from both of them. It is one of the most useful tools in linear algebra, physics, and engineering.

With this calculator, you can enter 3D or 2D vectors using numbers, fractions, or even symbols like a, b, and c. It gives you the full result in component form and î, ĵ, k̂ notation. You also get the magnitude, the angle between the vectors, the parallelogram area, the triangle area, the dot product, and the unit normal vector. A clear, step-by-step solution shows you exactly how the answer is found using the determinant method.

The tool also draws a 3D vector diagram, a right-hand rule chart, and a bar graph that compares each component side by side. You can check your own work with the built-in answer verifier. Whether you are a student learning vectors for the first time or solving a homework problem, this cross product calculator makes the work fast and simple.

How to Use Our Cross Product Calculator

Enter two vectors and this calculator will find their cross product. You will get the result in component form and i, j, k notation, a step-by-step solution, the magnitude, the angle between the vectors, and helpful diagrams.

Input Method: Pick how you want to type your vectors. Choose Structured Fields to enter each part of the vector in its own box. Choose Expression to type the full problem in one line, like (1, 2, 3) × (4, 5, 6).

Dimension: Pick 3D if your vectors have three parts (x, y, z). Pick 2D if they only have two parts (x, y). In 2D mode, the result is a single number along the z-axis.

Vector A: Enter the x, y, and z values for your first vector. You can use whole numbers, decimals, fractions like 3/4, or even letters like a for symbolic math.

Vector B: Enter the x, y, and z values for your second vector using the same format as Vector A.

Quick Presets and Examples: Click any preset or example button to load a ready-made problem and see how the calculator works.

Prefer Exact Fractions: Turn this on to show results as fractions instead of decimals. This is useful when your inputs are fractions.

Round Decimals: Turn this on and choose how many decimal places you want in the output.

Show Angle θ: Check this box to see the angle between Vector A and Vector B in degrees and radians.

Show Right-Hand-Rule Diagram: Check this box to display a picture that shows which way the cross product points using the right-hand rule.

Show 3D Vector Diagram: Check this box to see all three vectors drawn on a 3D set of axes. This only works in 3D mode.

Calculate: Press the Calculate button to get your answer. Press Reset to clear everything and start over.

Check Your Answer: Type your own answer into the verify box and click Verify to see if it matches the correct cross product.

What Is a Cross Product?

The cross product is a math operation that takes two vectors and gives you a brand new vector. This new vector points in a direction that is perpendicular (at a right angle) to both of the original vectors. Think of it like this: if two arrows lie flat on a table, their cross product points straight up from the table.

How the Cross Product Works

To find the cross product of two 3D vectors A = ⟨a₁, a₂, a₃⟩ and B = ⟨b₁, b₂, b₃⟩, you use this formula:

  • x-component: a₂ · b₃ − a₃ · b₂
  • y-component: a₃ · b₁ − a₁ · b₃
  • z-component: a₁ · b₂ − a₂ · b₁

This comes from finding the determinant of a 3×3 matrix made up of the unit vectors î, ĵ, and the components of your two vectors.

Key Properties of the Cross Product

The cross product has a few important rules:

  • Anti-commutative: Swapping the order flips the sign. A × B = −(B × A).
  • Perpendicular result: The answer is always at a right angle to both input vectors.
  • Parallel vectors give zero: If two vectors point in the same or opposite direction, their cross product is the zero vector ⟨0, 0, 0⟩.
  • Direction follows the right-hand rule: Curl the fingers of your right hand from A toward B. Your thumb points in the direction of A × B.

What the Magnitude Tells You

The length (magnitude) of the cross product equals the area of the parallelogram formed by the two vectors. Half of that value gives you the area of the triangle they form. The formula is |A × B| = |A| · |B| · sin(θ), where θ is the angle between A and B. You can use our trig calculator to evaluate the sine function for specific angles.

2D Cross Product

In two dimensions, vectors have no z-component. The cross product simplifies to a single number: a₁ · b₂ − a₂ · b₁. This scalar tells you the signed area of the parallelogram. A positive value means B is counterclockwise from A, and a negative value means B is clockwise from A.

Where Cross Products Are Used

Cross products show up in physics and engineering all the time. They help calculate torque (rotational force), the magnetic force on a moving charge, and surface normals in 3D graphics. Any time you need a direction that is perpendicular to a surface or a plane, the cross product is the tool to use. The closely related dot product is another essential vector operation that measures how much two vectors point in the same direction rather than producing a perpendicular vector.


Formulas used

Cross Product (Determinant Form)
\vec{A} \times \vec{B} = \begin{vmatrix} \hat{i} & \hat{j} & \hat{k} \\ a_x & a_y & a_z \\ b_x & b_y & b_z \end{vmatrix}
Cross Product Components
\vec{A} \times \vec{B} = \langle a_y b_z - a_z b_y,\; a_z b_x - a_x b_z,\; a_x b_y - a_y b_x \rangle
Magnitude of the Cross Product
|\vec{A} \times \vec{B}| = \sqrt{c_x^2 + c_y^2 + c_z^2}
Angle Between Vectors
\theta = \operatorname{atan2}\!\left(|\vec{A} \times \vec{B}|,\; \vec{A} \cdot \vec{B}\right)
Dot Product
\vec{A} \cdot \vec{B} = a_x b_x + a_y b_y + a_z b_z
Unit Normal Vector
\hat{n} = \frac{\vec{A} \times \vec{B}}{|\vec{A} \times \vec{B}|}
Triangle Area
A_{\triangle} = \frac{1}{2}\,|\vec{A} \times \vec{B}|

Frequently asked questions

What is the difference between a cross product and a dot product?

A cross product gives you a new vector that is perpendicular to both input vectors. A dot product gives you a single number (a scalar) that tells how much two vectors point in the same direction. This calculator computes both so you can compare them side by side.

Can I enter fractions into the cross product calculator?

Yes. Type fractions like 3/4 or -1/2 into any input field. The calculator will keep results as exact fractions when the Prefer exact fractions option is turned on.

What does it mean when the cross product is zero?

A cross product of ⟨0, 0, 0⟩ means the two vectors are parallel (pointing the same way) or anti-parallel (pointing opposite ways). It can also mean one or both vectors are the zero vector. The calculator will show a warning when this happens.

How do I use the calculator for 2D vectors?

Click the 2D (x, y) button under Dimension. The z-component is set to 0 automatically. The result is a single scalar number along the z-axis, which equals Aₓ · Bᵧ − Aᵧ · Bₓ.

What is the right-hand rule?

The right-hand rule tells you which way the cross product vector points. Point your fingers along vector A, then curl them toward vector B. Your thumb points in the direction of A × B. The calculator draws a diagram that shows this for you.

Can I type letters instead of numbers?

Yes. The calculator supports symbolic input. You can enter letters like a, b, or c as vector components. The result and steps will be shown using those symbols. Magnitude, angle, and diagrams are not available for symbolic inputs.

What is the unit normal vector shown in the results?

The unit normal vector (n̂) is the cross product divided by its magnitude. It has a length of exactly 1 and points in the same direction as A × B. It is useful when you need just the direction, not the size.

Why does switching the order of the vectors flip the sign?

The cross product is anti-commutative. That means B × A = −(A × B). The result vector points in the opposite direction when you swap the two vectors. The calculator shows both A × B and B × A so you can verify this property.

How do I check my homework answer with this tool?

Enter your two vectors and press Calculate. Then open the Check Your Answer section at the bottom. Type your answer into the box and click Verify. The calculator will tell you if your answer is correct or show you the right one.

How is the angle between two vectors calculated?

The calculator uses both the cross product magnitude and the dot product. It applies the formula θ = atan2(|A × B|, A · B), which gives the angle in degrees and radians. Turn on the Show angle θ option to see it.

What does the parallelogram area mean?

The magnitude of the cross product equals the area of the parallelogram formed by vectors A and B. The triangle area is exactly half of that. These are geometric meanings of the cross product that are useful in physics and engineering.

Can I use the expression input to type a problem in words?

Yes. Switch to Expression mode and type something like cross product of (1, 2, 3) and (4, 5, 6). The calculator will parse your input and compute the result. You can also use the × symbol between two vectors.

What happens if I enter a zero vector?

The cross product of any vector with the zero vector ⟨0, 0, 0⟩ is always the zero vector. The angle and unit normal will be listed as undefined because the zero vector has no direction.

Does the calculator show its work?

Yes. The Step-by-Step Solution section walks you through every part of the calculation. It shows the 3×3 determinant setup, expands each component (x, y, z), and assembles the final answer with full math notation.

What does the 3D vector diagram show?

The 3D diagram draws Vector A (solid purple), Vector B (dashed green), and A × B (dotted orange) from the origin on three axes. It helps you see how the cross product is perpendicular to both input vectors. This diagram only appears in 3D mode.