A free Mathcad alternative that runs in your browser

What a calculation looks like

You write the calculation as plain text. A quantity has a name, a value or formula, an optional unit to show it in, and a note after a bar:

# Beam moment

L: 6 m | span
w: 12 kN/m | design load
M: w * L^2 / 8 -> kN*m | maximum moment

The page shows the formulas typeset as maths, with your numbers substituted and the result in the unit you asked for. Here the moment comes out as 54 kN·m, because the engine multiplies and divides the units rather than trusting a label. A length added to a time is refused with a message, not silently summed.

Text between the calculations is Markdown, and formulas in LaTeX are typeset too. There is a plot command, input forms (a number box, a drop-down, radio buttons, a checkbox), vectors and matrices, a function library for solving, interpolation and integration, small Python blocks, and a symbolic dialog for exact algebra.

What you get that Mathcad users usually ask for

• Real units. Entered as 12 kN/m or 300 MPa, converted and combined by the engine.
• A report. Print to PDF, or export Word (with real Word equations) or Excel (with the workings and native charts).
• Offline. The page can be installed as an app and calculates without a connection.
• Privacy. The engine is compiled to WebAssembly and runs in the page. A calculation is not sent to a server.
• No cost, no account. The source is public and the licence is MIT.

Where it is different

A worksheet here is a document that runs from top to bottom, like a page of text with calculations in it. Mathcad lets you place regions anywhere on a canvas. If you rely on that free layout, expect to re-flow the page. You also write formulas as text lines and see them typeset in the result, rather than building them in an equation editor, although there is an on-screen maths keyboard for touch screens.

The symbolic side is smaller. The symbolic dialog does exact rational algebra with documented limits: it simplifies, expands, factors, differentiates, integrates a small class of integrands and solves equations of degree 1 and 2, and it has no complex numbers. If your worksheets lean on a full computer algebra system, this is not a replacement for it.

The product is young. Check anything you will rely on against a hand calculation or a result you already trust, as you would with any new tool.

Bringing your worksheets across

The page can read Mathcad worksheet files (.xmcd and .mcdx) and write them out as a new sheet that its own engine then calculates. It translates; it does not evaluate. Text, definitions, evaluations, functions, units, vectors and matrices, sums, integrals, programs made of loops and conditions, simple x-y plots, solve blocks of one or two unknowns and pictures convert. Regions it cannot convert (add-in functions, embedded objects, symbolic evaluation, some plot types) are shown as a picture of the original and counted in a summary, so you see what needs rebuilding.

Read how the converter works and where it stops before you trust a converted file. Plan on checking it against the source, line by line.

When Mathcad is still the better choice

Keep it if your worksheets call add-in libraries, embed other objects, depend on symbolic evaluation, or sit in a team library that a whole office edits with the same tool. The importer reports those as gaps, and no import will make them work. A good trial is to import one real worksheet, then compare every result with the original.