Scientific calculator

A calculator that shows the whole expression

Unlike a pocket calculator, this one keeps the entire expression on screen and evaluates it as you type. You can see what you entered, fix a bracket in the middle of it and watch the result change straight away.

It knows the usual functions — sin, cos, tan and their inverses, ln, log, sqrt, powers, factorial and the constants π and e. Trigonometry can run in degrees or radians; the switch is above the display, because picking the wrong one is the classic reason an answer comes out wrong.

You can type on the keyboard instead of using the pad, and multiplication can be implied: 2π and 3(4) both work.

Frequently asked questions

Does it respect the order of operations?

Yes. Multiplication and division come before addition and subtraction, powers before those, and brackets before everything. 2 + 3 × 4 gives 14, not 20.

Degrees or radians?

Use degrees for geometry and everyday angles, radians for calculus and physics. sin(30) is 0.5 in degrees but −0.988 in radians, so it is worth checking the switch before trusting a result.

How precise is it?

It computes in double precision and rounds the display to twelve significant digits, which hides the floating-point noise that would otherwise turn 0.1 + 0.2 into 0.30000000000000004.

Is anything sent anywhere?

No. The parser and the evaluation both run in your browser, so nothing you calculate leaves the page.