Kalkules is a free and portable scientific calculator for Windows which shows that isn’t necessarily true.
The program opens much like Windows’ own Calculator, with a numeric keypad and various buttons for basic operators and more advanced functions.
But if you don’t need all those options, clicking the Up arrow (top right) hides most of the interface. Clicking View > Always On Top leaves you with a data entry box where you can run simple calculations as necessary.
Data you enter is freely editable. Type 2*3, press Enter and you’ll see the result, but you can then edit the calculation like a line of text – changing any of the values, or the operator, or adding other figures – and press Enter to see the new result.
If you find you’re repeatedly entering the same lengthy figure – for example, a distance, 2.14562 – then you can save more time by using a variable.
There’s no need to think ahead, just type something like “d/60“. Kalkules doesn’t know what d means, so opens its Variables dialog with a blank box for “d”.
Enter the actual value 2.14562, click Calculate and the program displays the results. After that, you can type d in any equation and Kalkules will use the value you’ve assigned.
A built-in Expression Browser takes this further, making it easier to access various preset formulae (or add your own).
Browse to 3D > Sphere > Volume, for instance, and not only will you see the appropriate expression – V=(4/3)*$pi*r^3 – but you can also run that calculation by clicking Use and entering your sphere radius.
Whatever you’ve been doing, the History window displays all your recent calculations in one place. You can reuse any of these individually, or save an entire session for access later (or maybe sharing with someone else).
Handy bonus tools include a unit converter, which gives quick and easy conversions for length, angle, area, energy, mass, temperature and more.
If you need real math power then you’ll appreciate support for real, complex, and modulo numbers, bin/ oct/ dec/ hex calculations, simple function graphing, polynomials, quadratics and more.
The program does its best to keep operations simple, though. So if you’re an expert you might click Tools > Statistics, and calculate dispersion by entering values and weights. But everyone else can just accept the default settings, enter a few values in a column, and read their sum, average and median results.
Kalkules can’t compete with spreadsheets or the high-end calculating competition, but overall it’s a nicely judged tool, with plenty to offer experts and novices alike. Give it a try.