Calculators / Quick tool

Matrix Determinant Calculator

Calculate a two-by-two or three-by-three determinant from numeric rows.

● Processed locally in your browser
Processed locally in your browser
Determinant Choose an action to process the input.
How to useHow to use Matrix Determinant Calculator

What the tool actually does

Calculate a two-by-two or three-by-three determinant from numeric rows.

Reproducible example

Example input
1,2
3,4
Expected result
Determinant: -2
Formula: det(A) = ad − bc
Substitution: 1 × 4 − 2 × 3 = -2
  1. 1

    Paste content, enter parameters or choose the files you need in “Comma-separated matrix rows”.

  2. 2

    Choose “2×2 determinant”, “3×3 determinant” for the job. Processing runs in this browser.

  3. 3

    Review the result under “Determinant”, then copy or download it after checking the output.

Result guide

What Matrix Determinant Calculator calculates

Choose the matrix size, enter one comma-separated row per line, and calculate det(A). The output shows the 2×2 diagonal formula or the 3×3 first-row cofactor expansion with your values substituted.

2×2 determinant formula

For A = [[a,b],[c,d]], det(A) = ad − bc. For the sample [[1,2],[3,4]], the determinant is 1×4 − 2×3 = −2.

3×3 cofactor expansion

For the first row a, b, c, use a(ei−fh) − b(di−fg) + c(dh−eg). The result panel preserves this grouping so signs and each 2×2 minor can be checked directly.

What a zero determinant means

A zero determinant means the square matrix is singular: it has no unique inverse, its rows or columns are linearly dependent, and a related linear system may not have a unique solution.

Frequently asked questions

What input format should I use?

Enter one matrix row per line and separate entries with commas. A 3×3 matrix therefore needs exactly three lines with three numeric values on each line.

Does this calculator support larger matrices?

No. This page intentionally supports only 2×2 and 3×3 numeric matrices so it can show a compact, verifiable substitution. It does not claim support for symbolic or larger matrices.

Can a determinant be negative?

Yes. A determinant is a signed scalar. Its sign can reflect orientation, while its absolute value describes area or volume scaling for the linear transformation.