Column Space Calculator Calculator

Column Space Calculator

Find the column space basis and determine the rank of any matrix.

Last updated: 2026-05-24T22:58:31.717Z

Enter matrix entries as numbers; decimals allowed.

Rank

0

Nullity

3

Column Space Basis Vectors:

Zero matrix - no basis vectors

What is Column Space?

The column space (also called the range) of a matrix is the set of all linear combinations of its column vectors. It represents all possible outputs of the matrix when multiplied by any input vector. Geometrically for a 3×3 matrix, the column space can be a plane, a line, or just the origin.

A basis for the column space is a set of linearly independent vectors that spans all vectors in the column space. The rank of a matrix equals the dimension of its column space, which equals the number of pivot columns in row echelon form.

How to Find Column Space

Method: Row Reduction

1. Reduce matrix to row echelon form
2. Identify pivot columns
3. Original columns at pivot positions form basis
Basis = pivot columns of original matrix

Key Properties

  • • Dimension = rank of matrix
  • • Contains zero vector always
  • • Closed under addition & scalar multiplication
  • • Rank + Nullity = Number of columns
  • • Forms a subspace of ℝᵐ (m = number of rows)

Worked Example

Find the column space basis of:

⎡ 1 2 3 ⎤

⎢ 2 4 6 ⎥

⎣ 3 6 9 ⎦

Step 1: Reduce to row echelon form

Step 2: Pivot columns are: 1 (column 1 only)

Step 3: Rank = 1, Nullity = 2

Column space basis: {[1, 2, 3]}

Frequently Asked Questions

Can column space be empty?

No. The zero vector is always in the column space, so it's never empty.

How do I find nullity?

Nullity = Total columns - Rank. It's the dimension of the null space.

Why use original columns as basis?

Row operations preserve column space, so pivot columns of the original matrix form the basis.

What if rank = number of rows?

The column space spans the entire ℝⁿ (where n = number of rows). This matrix has full row rank.

Is column space always a plane?

Not always. For a 3×3 matrix, it could be 3D space, a plane, a line, or just a point (origin).

How does this relate to linear systems?

Ax = b has a solution only if b is in the column space of A.

Can basis vectors be dependent?

No. By definition, basis vectors are linearly independent.

What's the difference from row space?

Row space uses row vectors; column space uses column vectors. They have equal dimension (rank).

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