Scientific calculator. Real math, safely parsed.

How to use the Scientific Calculator

This calculator works out full expressions with trig, logarithms, powers, roots, factorials, pi and e. A small parser reads what you enter, follows the normal order of operations and parentheses, and shows the answer live as you go. Use it for schoolwork, engineering checks or any calculation too long for a basic calculator.

Step by step

1. 1
   Set the angle unit

   Choose DEG or RAD before you use sin, cos or tan. DEG is selected when the page opens, so sin(30) gives 0.5. In RAD the same answer needs sin(pi/6).

2. 2
   Enter the expression

   Tap the keys or type on your keyboard. The keyboard covers digits, the decimal point, plus, minus, times, divide, ^, parentheses, ! and %. Functions such as sin and log are on the pad only. The small line shows the expression and the big line a live answer.

3. 3
   Use functions and constants

   Keys such as sin, log, ln and the root keys open a parenthesis for you; close it with ). Use the x² and xʸ keys for powers, n! for factorials and π or e for the constants. 1/x takes the reciprocal of the whole entry and shows the answer at once. Most keys show their name when you hover over them.

4. 4
   Switch to inverse trig

   Press 2nd to turn sin, cos and tan into sin⁻¹, cos⁻¹ and tan⁻¹, and press it again to switch back. Inverse results come back in the angle unit you chose.

5. 5
   Get the answer

   Press = or Enter. An operator pressed next carries the answer into a new calculation, while a digit or a function starts fresh. Use the backspace key on the pad or Backspace to delete, and AC, Esc or Delete to clear the expression. Clearing leaves memory and History as they are.

6. 6
   Use memory and history

   M+ adds the current value to memory and M− subtracts it, MR inserts the stored value and MC clears it; an M badge shows while memory holds a number. The last 50 answers appear under History, and clicking one loads it as your new starting value.

Reading the result

• Answers are rounded to 12 significant figures. Numbers from 10^15 up, or smaller than 10^-9, are shown in scientific notation, such as 1.2e+20.
• If something is wrong when you press =, a red message replaces the answer, for example Cannot divide by zero, log needs a value > 0 or Factorial needs a whole number ≥ 0.
• Factorials above 170 return ∞, because the result is too large for the calculator to hold.
• Powers bind tighter than a leading minus, so -3^2 is -9. Write (-3)^2 to square a negative number.

Tips and common mistakes

• The % key gives the remainder after division, not a percentage. 10%3 is 1, and 50% on its own is an error. To take 15% of 80, enter 0.15*80.
• A function key pressed right after = starts a new expression. To use the answer inside a function, press MC, then M+, then the function key, MR and ).
• You can leave out the times sign before an opening parenthesis, a constant or a function, as in 2(3), 2π or 3sin(30). A plain number cannot follow a closing parenthesis, so write (2)*3 rather than (2)3.
• A number followed by the e key and a whole number is read as scientific notation, so 1.2e-3 is 0.0012. That also means 2e-3 is 0.002, not 2 times e minus 3. Write 2*e-3 for the second.

Privacy and limits

Every expression is evaluated in your browser by the page's own parser and never sent anywhere. History and memory are kept only while the page is open, so they are gone when you reload or close the tab.

Back to the tool

Everything a scientific calculator should do.

• Evaluate trig expressions in DEG or RAD mode, sin, cos, tan and their inverses via the 2nd key.
• Compute logs, powers and roots: base-10 log, natural log, square root, cube root, squares and arbitrary powers with x^y.
• Use factorials, π and e, plus implicit multiplication, so 2π, 2(3) and 3sin(30) just work.
• Store values in memory with MC, MR, M+ and M−, with an on-display indicator while something is stored.
• Reuse your history: the last 50 calculations stay on-screen, click any entry to load its result as your new starting value.
• Type freely with your keyboard: digits, operators, parentheses, Enter to evaluate, Backspace to delete, Esc to clear, with a live result preview as you type.

Frequently asked questions.

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