Unlimited Calculator

A tape you can edit. Exact fractions, units that carry through every step, and a computer algebra system in one text field. No account, no subscription.

A tape you can edit, arithmetic that refuses to round when it doesn't have to, units that carry through every step, and a computer algebra system behind the same text field.

Type an expression and press Return. The answer appears beside it, and the line stays there: editable. Change any line and everything below it updates, which is what makes this a tape rather than a display.

The window has three parts: a searchable library of every function, unit, and constant on the left; the tape in the middle; and an inspector on the right showing the selected line's other forms, unit conversions, and a graph when it has a free variable.

EXACT BY DEFAULT 1/3 + 1/6 answers 1/2, not 0.5000000000000001. A fraction stays a fraction, an integer grows as large as it needs to, and a decimal you typed is read as the number you wrote. An answer that isn't exact is marked with ≈. That mark is the whole promise: without it, what you're looking at is exactly right.

• 200! gives 375 digits, all of them
• 2^1000 gives just as many
• isprime(2^61 - 1) returns true, tested not guessed
• 1/7, then float(1/7, 40) gives forty correct digits

UNITS THAT CARRY THROUGH Write the unit after the number and it comes along for the ride: 3.5 ft to m, 60 mph * 2 h to mi, 100 degC to degF. Adding metres to kilograms is an error, not a number: dimensions are checked on every operation. Two hundred units are built in, across length, mass, time, area, volume, pressure, energy, power, force, speed, data, angles, temperature, plus astronomical, nuclear, molar, and aviation units.

ALGEBRA, NOT JUST ARITHMETIC The same field takes expressions with unknowns: expand, diff, integrate, limit, solve, series. solve answers exactly wherever an exact answer exists: solve(x^2 = 2, x) gives ±√2, not a decimal.

NAME THINGS k = 3 binds a name; f(x) = x^2 + 1 defines a function. Change a definition and every line that used it recomputes. Select a name = number line and the inspector grows an Adjust slider you can drag: a live knob on any figure in the tape.

EVERYWHERE ELSE A quick calculator lives in the menu bar for quick answers that never touch your tapes. And because the engine reaches anywhere text does, select an expression in any app and choose Calculate with Unlimited Calculator from the Services menu.

Also included: integers of any size, exact fractions, complex numbers, every base from 2 to 36, 243 built in functions, percentages and running totals, loan schedules, multiple tapes, date and currency arithmetic, and reverse Polish entry.

Every computation runs on this Mac, in this app's own code. No account, no subscription, no ads, no analytics, no tracking. Nothing is ever sent anywhere.