Generate a Diagonal Matrix
Elements only on the diagonal. Runs entirely in your browser, so your data never leaves your device.
Output
The result appears here as you type.
How to use Generate a Diagonal Matrix
- 1. Type the diagonal values. Enter Diagonal values as comma-separated numbers, such as 1, 2, 3. The count of values you enter also determines the matrix size, since a diagonal matrix is always square.
- 2. See how the matrix fills in. Each value you typed lands on the main diagonal in order, from top-left to bottom-right, while every other cell is automatically set to zero.
- 3. Copy the generated matrix. Copy the text grid, with rows separated by line breaks, into a linear algebra tool, homework document or spreadsheet that expects a diagonal matrix as input.
When to use Generate a Diagonal Matrix
Generate a Diagonal Matrix builds a square matrix with your chosen values on the main diagonal and zeros everywhere else. It is for any situation where you need a specific diagonal matrix quickly instead of typing out the zeros by hand.
- Building an eigenvalue example. A diagonal matrix's eigenvalues are exactly its diagonal entries, so typing in 1, 2, 3 gives you an instant example matrix for teaching or practicing eigenvalue computation.
- Constructing a scaling transform. In computer graphics or linear algebra, a diagonal matrix scales each axis independently. Typing the desired scale factors produces the transform matrix directly, without manual zero-padding.
- Testing a matrix inversion function. Diagonal matrices invert trivially by taking the reciprocal of each diagonal entry, making them a convenient known-answer test case for a matrix inversion routine.
- Demonstrating matrix multiplication shortcuts. Multiplying by a diagonal matrix just scales rows or columns, so building one with specific values helps show students the shortcut compared to full matrix multiplication.
Examples
The diagonal matrix of 1, 2, 3
Output
1 0 0 0 2 0 0 0 3
About the Generate a Diagonal Matrix tool
Generate a Diagonal Matrix runs as plain JavaScript in your browser tab, with no server behind it. Elements only on the diagonal. Whatever you put in stays on your device from start to finish.
The tool is part of EditSafely's Math Tools section, 234 single-purpose utilities built around the same idea: open the page, get the result, keep your data to yourself.
You can shape the output with the Diagonal values setting, and the result refreshes the moment you change it. A worked example further down the page shows exactly what the tool produces for a real input.
That local-first design has practical benefits beyond privacy. The tool keeps working on a flaky connection once the page has loaded, results are instant because nothing round-trips to a server, and it is safe to use with confidential material.
Frequently asked questions
Does Generate a Diagonal Matrix cost anything?
Yes, it is completely free. All 2,658 tools on EditSafely work without an account, a subscription or usage limits.
Does the generator send anything to a server?
No data leaves your device. The whole tool is JavaScript that runs inside your browser tab, so there is no upload, no server-side processing and no log of what you did. If you disconnect from the internet after the page loads, it keeps working.
How do I get a different result?
Run the generator again. Each run is computed fresh on your device, and any options you change are applied to the next result immediately.
Do I need to sign up or install anything?
Nothing to install and no account needed. Open the page in any up-to-date browser, including on a phone or tablet, and the tool is ready.
How do I use the result?
The output panel has a one-click copy button, and you can keep refining the input while you work; the result updates in place as you type.