Math calculators

Basic Calculator

Updated Jun 20, 2026 By Jehan Wadia
Formulas
M   0

Works with your keyboard & numpad — Enter to evaluate, Esc to clear, Backspace to delete.

History

    Introduction

    This free online basic calculator lets you add, subtract, multiply, and divide numbers right in your browser. You can also use it to find square roots, work with exponents, and calculate percentages. It stores your past calculations in a history list so you can look back at your work. A built-in memory feature lets you save a number and recall it later. Just click the buttons or type on your keyboard to get started. The calculator shows your full expression and result at the same time, so you always know what you typed. It works on both desktop and mobile screens.

    How to Use Our Basic Calculator

    Type in numbers and pick an operation to get your answer right away. The top line shows your expression, and the bottom line shows the result.

    Number buttons (0–9): Press any digit to add it to your expression.

    Decimal point (.): Press the dot to enter a decimal number like 3.5 or 0.75.

    Add (+): Press the plus sign to add two numbers together.

    Subtract (−): Press the minus sign to take one number away from another.

    Multiply (×): Press the times sign to multiply two numbers.

    Divide (÷): Press the divide sign to split one number by another.

    Exponent (x^y): Press this to raise a number to a power, like 2^3 to get 8. For more advanced exponent work, try our dedicated Exponent Calculator.

    Square root (√x): Press this to find the square root of the last number you entered. For additional options, see our Square Root Calculator.

    Pi (π): Press this to insert the value of pi (3.14159…) into your expression. This is especially useful when calculating measurements like circumference or circle area.

    Percent (%): Press this to turn a number into a percent or to find a percent of another number. You can also use our Percentage Calculator for more detailed percentage work.

    Negate (+/−): Press this to switch the last number between positive and negative.

    Backspace (Back): Press this to erase the last character you typed.

    Clear (AC/CE): Press once to clear the current entry. Press again to reset the whole calculator.

    Equals (=): Press this or the Calculate button to see your final answer. Press it again to repeat the last operation.

    Ans: Press this to reuse the result from your last calculation in a new expression.

    Memory Add (M+): Press this to add the current value to memory.

    Memory Subtract (M−): Press this to subtract the current value from memory.

    Memory Recall (MR): Press this to place the stored memory value into your expression.

    Memory Clear (MC): Press this to erase the value stored in memory.

    Round to whole (R0 / RND): Press either button to round the current result to the nearest whole number. For more rounding options, try our Rounding Calculator.

    Round to 2 decimals (R2): Press this to round the current result to two decimal places.

    Reset: Press the Reset button to clear everything, including memory and history.

    Display Size: Use this dropdown to switch the calculator between small, medium, and large text.

    Layout: Use this dropdown to switch between a desktop view and a narrower mobile view.

    Keyboard support: You can also type numbers and operators on your keyboard. Press Enter to calculate, Backspace to delete, and Escape to clear.

    What Is a Basic Calculator?

    A basic calculator is a tool that helps you solve math problems quickly. You can add, subtract, multiply, and divide numbers without doing the work by hand. This calculator also lets you use exponents, square roots, and the number pi (π). If you need to work with fractions, logarithms, or scientific notation, we offer dedicated tools for those as well.

    How Basic Math Works

    Math uses four main operations: addition (+), subtraction (−), multiplication (×), and division (÷). These operations follow a set order. Multiplication and division are always done before addition and subtraction. This rule is called the order of operations. For example, in the problem 3 + 4 × 2, you multiply 4 × 2 first to get 8, then add 3 to get 11. For division problems that require step-by-step work, our Long Division Calculator can help you see the full process.

    Extra Features You Can Use

    Exponents let you multiply a number by itself. For example, 5^2 means 5 × 5, which equals 25. A square root does the opposite — it finds what number multiplied by itself gives you the original number. The square root of 25 is 5. You can also find cube roots using our dedicated tool.

    The percent button (%) turns a number into its decimal form or finds a percent of another number. This is useful for tips, discounts, and taxes. If you need to find the percent change or percent difference between two values, we have specialized tools for those calculations.

    Memory buttons let you save a number and use it later. Press M+ to store a value, MR to bring it back, and MC to clear it. The Ans button recalls your last answer so you can use it in a new problem without retyping it.

    Rounding buttons let you shorten long decimal answers. R0 rounds to a whole number, and R2 rounds to two decimal places. This is helpful when you need a clean, simple answer. For precise rounding rules, including significant figures, check out our specialized rounding tools. If you need to convert a decimal result into a fraction, try the Decimal to Fraction Calculator.


    Formulas used

    Addition
    a + b
    Subtraction
    a - b
    Multiplication
    a \times b
    Division
    a \div b
    Exponentiation
    a^{b}
    Square Root
    \sqrt{x}
    Percentage
    x\% = \frac{x}{100}

    Frequently asked questions

    Is this calculator free to use?

    Yes. This basic calculator is 100% free. There are no sign-ups, no limits, and no hidden fees. You can use it as many times as you want.

    Does the calculator follow the order of operations?

    Yes. It does multiplication and division before addition and subtraction, just like you learn in school. For example, if you type 2 + 3 × 4, it gives you 14, not 20.

    Can I use my keyboard instead of clicking buttons?

    Yes. Type numbers and operators like +, -, *, and / on your keyboard. Press Enter to get the answer, Backspace to delete, and Escape to clear everything.

    What happens if I divide by zero?

    The calculator shows an error message that says "Error: Divide by 0." You cannot divide any number by zero because it has no valid answer in math. Press AC or Escape to clear the error and start over.

    What is the difference between AC and CE?

    CE (Clear Entry) erases only the last number you typed. AC (All Clear) resets the whole calculator. The button switches between the two depending on what you have on screen.

    Does the calculator save my history after I leave the page?

    No. Your calculation history is only stored while the page is open. If you close or refresh the page, the history is erased. Write down any answers you need to keep.

    What does the Ans button do?

    The Ans button inserts the result of your last completed calculation into your current expression. This lets you chain calculations together without retyping the previous answer.

    How do I enter a negative number?

    Type the number first, then press the +/− button to make it negative. You can also start an expression with the minus sign to enter a negative number at the beginning.

    What does the yellow M indicator on the display mean?

    The yellow M badge means a number is stored in memory. It appears when you press M+ or M−. Press MC to clear memory and make the badge go away.

    How do I calculate a percentage of a number?

    Type the base number, press + or , type the percent value, then press %. For example, to find 20% of 50, type 50 × 20 then press % and =.

    Can I do multiple operations in one expression?

    Yes. You can type a long expression like 10 + 5 × 3 − 2 and the calculator will solve it all at once using the correct order of operations when you press =.

    What does pressing equals more than once do?

    Pressing = again repeats the last operation with the same number. For example, if you calculate 5 + 3 = 8, pressing = again adds 3 more to get 11, then 14, and so on.

    How accurate is this calculator?

    It is accurate up to about 10 decimal places. It automatically cleans up tiny floating-point errors that computers sometimes produce, so your answers stay precise for everyday math.

    Does this calculator work on phones and tablets?

    Yes. It works in any modern web browser on phones, tablets, and computers. You can also switch to the Mobile layout using the dropdown menu to get larger buttons on a smaller screen.

    How do I raise a number to a power?

    Type the base number, press the x^y button, then type the exponent. For example, type 2, press x^y, then type 5 and press = to get 32.

    What is the largest number this calculator can handle?

    It can handle numbers up to about 10308. If a result goes beyond that limit, the calculator shows an "Error: Overflow" message.