Typing or tapping
Type straight into the display with your keyboard, or tap the keys. Enter works out the answer, Esc clears, and Backspace deletes. Use * or × to multiply, / or ÷ to divide, and ^ for powers. Brackets left open are closed for you.
Order of operations
Brackets first, then powers, then multiplying and dividing, then adding and subtracting, the way you were taught: 2 + 3 × 4 is 14. A number written next to a bracket is multiplied by it, so 2(3 + 4) is 14. Minus binds after powers, so -3^2 is −9; write (-3)^2 for 9.
Exact answers
Ordinary arithmetic is done with exact fractions, not rounded binary numbers, so 0.1 + 0.2 is exactly 0.3 and 1/3 × 3 is exactly 1. When the answer is a fraction, it is shown as one under the decimal.
Percent
50 + 10% adds 10% of 50, giving 55, the way a till or a phone calculator does. 10% on its own is 0.1, and 20% × 80 is 16. For percentage questions in words, such as what percent one number is of another, use the Percentage Calculator.
Questions
What is Ans?
The last answer. Press an operator straight after an answer and the sum carries on from it; press Ans to use it anywhere. It is kept exactly, so carrying on from 1/3 does not lose any digits.
Does it have sin, cos and logs?
Yes: press Scientific to open the Scientific Calculator, with keys for trig, roots, powers, logs and factorials. Your sum and your history go with you, and Basic there brings you back.
Is my history saved?
Only while this page is open. Nothing you type is stored or sent anywhere, and closing the page clears it.