Math calculators

RREF Calculator

Updated Jul 9, 2026 By Jehan Wadia
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Matrix Configuration
Matrix configuration options
×
Integers from 1 to 10. Click “Generate Matrix” to apply new dimensions.
Quick Example Presets
Matrix Input

Type integers, decimals, or fractions (e.g. 2/3, -1.5) in each cell. Use Tab / Shift+Tab or ↑ ↓ arrow keys to move between cells; press Enter to calculate.


Introduction

This RREF calculator turns any matrix into reduced row echelon form or row echelon form (REF) using Gauss-Jordan elimination. Just type your numbers into the grid, press Calculate, and get the answer right away. The tool shows every row operation step by step so you can follow along and learn how the process works.

It works with both coefficient matrices and augmented matrices. You can enter whole numbers, decimals, or fractions like 2/3. The calculator finds the rank, pivot columns, free variables, and nullity of your matrix. For augmented matrices, it also tells you whether the system of linear equations has a unique solution, infinitely many solutions, or no solution at all.

All answers are computed using exact fractions, so you never lose accuracy to rounding. You can also switch to decimal mode if you prefer. Whether you are a student checking homework or a teacher preparing examples, this free online RREF calculator gives you clear, detailed results in seconds.

How to Use Our RREF Calculator

Enter your matrix values and settings below. The calculator will show the reduced row echelon form (RREF) or row echelon form (REF) of your matrix, along with step-by-step row operations, rank, pivot positions, and solution analysis.

Set your matrix size by typing the number of rows and columns (1 to 10 each) into the Rows and Columns fields, then click "Generate Matrix" to build the grid.

Choose the matrix type. Pick "Augmented" if your matrix includes a constants column on the right side (used for solving systems of equations). Pick "Coefficient" if your matrix has no constants column.

Select the output form. Choose "RREF" for the fully reduced row echelon form, or choose "REF" for the standard row echelon form.

Pick how values are shown. Use the "Display Values As" dropdown to see results as exact fractions or as decimals rounded to four decimal places. If you need to convert between these formats outside the calculator, try our Decimal to Fraction Calculator.

Enter your numbers into the grid. Type an integer, decimal, or fraction (like 2/3 or -1.5) into each cell. Use Tab, Shift+Tab, or the arrow keys to move between cells. Press Enter to calculate right away. For more complex fraction arithmetic, our Fraction Calculator can help.

Or paste a full matrix. Click "Paste a Matrix" to open a text box. Type or paste your matrix with values separated by spaces, commas, or tabs, and rows on separate lines. Then click "Load from Text" to fill the grid automatically.

Try a quick preset by clicking any example button (like "Unique Solution" or "No Solution") to load a sample matrix and see results instantly.

Click "Calculate" to run the row reduction. The calculator will display your original matrix, every row operation step by step, the final RREF or REF matrix with pivot positions highlighted, the rank and nullity, and a full solution analysis for augmented matrices.

What Is Reduced Row Echelon Form (RREF)?

Reduced row echelon form, or RREF, is a way to simplify a matrix so it is as easy to read as possible. A matrix is a grid of numbers arranged in rows and columns. When you put a matrix into RREF, you use simple row operations to reshape it until each leading number in a row is 1, every other number in that leading column is 0, and the leading 1s step to the right as you move down the rows.

What Are Row Operations?

To reach RREF, you only need three moves, called elementary row operations:

  • Swap — Switch two rows with each other.
  • Scale — Multiply every number in a row by the same non-zero value.
  • Replace — Add or subtract a multiple of one row from another row.

These operations change the look of the matrix but never change the solution of the system it represents.

REF vs. RREF

Row echelon form (REF) is a partially simplified version. It only requires zeros below each leading entry. Reduced row echelon form (RREF) goes further and also clears all numbers above each leading entry, making each leading entry equal to 1. RREF gives you the cleanest, most direct answer.

Why Does RREF Matter?

RREF is one of the most important tools in linear algebra. It lets you solve systems of linear equations, find the rank of a matrix, identify pivot and free variables, and determine whether a system has one solution, infinitely many solutions, or no solution at all. It is the standard method taught in algebra and college math courses for working with matrices by hand or with a calculator.

RREF is also closely related to other matrix operations. For example, knowing the rank helps you determine whether an inverse matrix exists, and the pivot structure connects directly to the determinant of a square matrix. If you need to perform other matrix operations like addition or scalar multiplication, our Matrix Calculator handles those tasks. For multiplying two matrices together, see our Matrix Multiplication Calculator.

Augmented vs. Coefficient Matrices

An augmented matrix includes the constants from the right side of a system of equations, separated by a vertical line. A coefficient matrix holds only the numbers in front of the variables. Use the augmented form when you want to solve a system. Use the coefficient form when you need the rank or other properties of the matrix alone.

Understanding the Results

After row reduction, the rank tells you how many independent equations exist. Pivot columns point to the leading variables, and the remaining columns point to free variables. If there are no free variables in an augmented system, the solution is unique. If free variables exist, there are infinitely many solutions. If a row reduces to something like 0 = 5, the system has no solution and is called inconsistent.

Once you know the solution type, you can explore related concepts. Use the Dot Product Calculator or Cross Product Calculator for vector operations that often come up alongside matrix work. For individual equations rather than full systems, the Solve For X Calculator can isolate a single variable quickly.


Formulas used

Row Swap (Elementary Row Operation)
R_i \leftrightarrow R_j
Row Scaling to Create Leading 1
R_i \to \frac{1}{a_{i,\,p}} \cdot R_i
Row Replacement (Elimination)
R_i \to R_i - \frac{a_{i,\,p}}{a_{k,\,p}} \cdot R_k
Rank–Nullity Theorem
\text{nullity}(A) = n - \text{rank}(A)
Fraction Reduction via GCD
\frac{a}{b} = \frac{a \div \gcd(a,\,b)}{b \div \gcd(a,\,b)}

Frequently asked questions

What values can I type into the matrix cells?

You can type whole numbers (like 5 or -3), decimals (like 1.5 or -0.25), or fractions (like 2/3 or -7/4). Every cell must have a value before you click Calculate.

What is the maximum matrix size this calculator supports?

The calculator handles matrices up to 10 rows by 10 columns. Type your desired size into the Rows and Columns fields and click Generate Matrix to build the grid.

Can I use this RREF calculator on my phone?

Yes. The grid scrolls sideways on small screens so you can reach every cell. Use Tab or tap each cell to enter values. The calculator works in any modern mobile browser.

What do the colored badges on each step mean?

Each step has a colored label that tells you which row operation was used:
  • Swap (purple) — two rows switched places.
  • Scale (green) — a row was multiplied by a number to make the pivot equal to 1.
  • Replace (orange) — a multiple of one row was added to or subtracted from another row to create a zero.

What does the yellow highlight on a cell mean?

A yellow highlighted cell marks a pivot position. Pivots are the leading 1s (in RREF) or leading entries (in REF) that define the structure of your matrix. They show which columns hold basic variables.

How do I paste a matrix from a spreadsheet or text file?

Click the Paste a Matrix button to open the text box. Paste your data with columns separated by spaces, commas, or tabs. Put each row on a new line. Then click Load from Text and the grid will fill in automatically.

Are the fraction results exact?

Yes. The calculator uses exact fraction math internally, so there is no rounding error. If you switch the display to decimals, the values are rounded to four decimal places for display only.

What is the difference between rank and nullity?

The rank is the number of pivot columns, which tells you how many independent equations or directions the matrix has. The nullity is the number of non-pivot (free) columns. Together they always add up to the total number of columns in the coefficient part of the matrix.

When should I choose Coefficient instead of Augmented?

Choose Coefficient when your matrix has no constants column and you only want the rank, RREF, or other properties of the matrix itself. Choose Augmented when the last column holds the constants from a system of equations and you want to solve that system.

Why does the calculator say my system has no solution?

The system has no solution when a row reduces to all zeros on the left side but a non-zero number on the right side, like 0 0 0 | 5. That row says 0 = 5, which is impossible, so no values of the variables can satisfy every equation at once.

What are free variables?

Free variables are the variables whose columns do not contain a pivot. They can take any value, and the other (basic) variables are written in terms of them. Free variables appear when a system has infinitely many solutions.

Can I copy the result to use somewhere else?

Yes. Click the Copy Result Matrix button to copy the final RREF or REF matrix to your clipboard. You can also click Copy All Steps to copy every row operation and intermediate matrix as plain text.

Does this calculator show work I can turn in for class?

The step-by-step section shows every row operation with a description, the math notation, and the matrix after each step. You can use this as a guide to write out your own work. Always check with your teacher about what format they expect.

What happens if I leave a cell empty?

The calculator will show an error message and highlight the empty cell in red. Every cell must contain a valid number or fraction before you can calculate.

Can I hide the step-by-step solution?

Yes. Use the Show Steps toggle at the top of the Step-by-Step Solution section to hide or show all the intermediate steps. The final result and analysis sections stay visible.