Scientific calculator
Type or tap a sum: the answer, how it was read, and every step
Type with your keyboard or tap the keys. The answer updates as you go; press = or Enter to keep it in the list below.
On a keyboard: * for ×, / for ÷, ^ for a power, Enter for =, Esc to clear.
–
- How the calculator read it
- –
- As an exact fraction
- –
Working, step by step
Answers kept this visit
Press = or Enter to keep an answer here. Nothing is saved after you close the page.
The order the calculator works in
It follows the order taught in schools (BIDMAS, BODMAS or PEMDAS): brackets first, then powers and roots, then multiplication and division from left to right, then addition and subtraction from left to right. So 2 + 3 × 4 is 14, not 20. The "How the calculator read it" line adds brackets to show exactly what was worked out, and the steps list each sum in the order it was done.
Points worth knowing
- Powers are worked from the right: 2^3^2 is 2^9 = 512.
- A minus sign in front applies after the power: −2² is −4. Type (−2)² for 4.
- A number next to a bracket multiplies it, at the same level as ×: 6 ÷ 2(1 + 2) is 6 ÷ 2 × 3 = 9. Add brackets if you mean 6 ÷ (2 × 3).
- A % after a number divides it by 100. After + or −, it is a percentage of the number before, as on a phone calculator: 50 + 10% is 55.
- Choose Degrees or Radians before using sin, cos or tan. tan(90°) has no answer, and the calculator says so.
- E means "times ten to the power of": 2E3 is 2000.
Exact answers, and when they are not
Ordinary computer arithmetic gets 0.1 + 0.2 slightly wrong. This calculator keeps numbers as exact fractions for +, −, ×, ÷ and whole-number powers, so it gives exactly 0.3, and 1 ÷ 3 × 3 is exactly 1. Square roots that do not come out, sines, logs and anything using π cannot be exact; those answers are rounded to 12 significant digits and shown with ≈.
Formula and sources
- Order of operations: Common Core 6.EE.A.2c (whole-number exponents and the conventional order when there are no brackets); square and cube roots 8.EE.A.2.
- The percent key follows the common phone-calculator rule (a + b% = a + a × b ÷ 100).
- Floating point for functions with no exact answer: IEEE 754 double precision, about 15 to 17 significant digits, rounded here to 15 inside and 12 on screen.
- Checked in test_maths.js against worked examples: 0.1 + 0.2 = 0.3; 0.1 × 3 − 0.3 = 0; 2 + 3 × 4 = 14; 2^3^2 = 512; −2² = −4; 6 ÷ 2(1 + 2) = 9; sin 30° = 0.5; cos 60° = 0.5; tan 45° = 1; sin π = 0 in radians; √16 = 4; ∛−27 = −3; log 1000 = 3; 20! = 2,432,902,008,176,640,000; 50 + 10% = 55; division by zero is refused.