Basic Calculator

What Can This Online Calculator Do?

This free online calculator handles all everyday arithmetic — addition, subtraction, multiplication and division — plus a set of extra functions you'd find on a physical desk calculator. Whether you're splitting a bill, working out a percentage discount or doing a quick unit conversion, you get instant, accurate results without installing anything.

Beyond the four basic operations, the calculator supports: square root (√) for finding roots instantly, percentage (%) for tax and discount calculations, sign toggle (±) to negate any number, parentheses ( ) for grouping expressions, and memory functions to carry a value across multiple calculations. Every completed calculation is saved in the history panel so you can review or reuse past results at any time.

How to Use the Online Calculator

1. Enter a number by clicking the digit buttons or typing on your keyboard.
2. Press an operator (+, −, ×, ÷) to set the operation.
3. Enter the second number, then press = or Enter.
4. The result appears instantly. It is also saved to the history panel below the calculator.
5. Press AC to clear everything and start a new calculation.
6. Use ⌫ to delete the last digit if you made a typo.

Memory Functions Explained

The memory row lets you store an intermediate result and reuse it without retyping:

• M+ — adds the current display value to memory.
• M− — subtracts the current display value from memory.
• MR — recalls the stored memory value to the display.
• MC — clears memory to zero. The purple M indicator on the display lights up whenever memory holds a non-zero value.

Example: You want to add three separate numbers (245, 180, 97). Press 245 = M+, then 180 = M+, then 97 = M+, then MR. The display shows 522 — the running total stored in memory.

How Percentage Works

Press a number then % to convert it to its decimal equivalent (50 % = 0.5). More usefully, within a running calculation:

• 200 + 10 % → adds 10% of 200, giving 220.
• 500 − 15 % → subtracts 15% of 500, giving 425.
• 1200 × 8 % → calculates 8% of 1200, giving 96.

Order of Operations (BODMAS / PEMDAS)

The calculator evaluates expressions using standard mathematical precedence — brackets first, then division and multiplication (left to right), then addition and subtraction (left to right). Use ( ) to explicitly control the order when you need it. For example: 3 + 4 × 2 = 11 (multiplication first), but (3 + 4) × 2 = 14 (brackets first).

Frequently Asked Questions

What is an online calculator?

An online calculator is a free, browser-based arithmetic tool that performs mathematical computations without any download or installation. This basic online calculator supports addition, subtraction, multiplication, division, square root, percentage, memory storage, and parentheses for grouped expressions.

Is this online calculator free?

Yes — completely free, no sign-up or account required. All calculators on Calculator Junction are 100% free to use on any device.

Can I use this calculator on mobile?

Yes. The calculator is fully responsive and works on smartphones, tablets, and desktops. The buttons are sized for easy touch input on mobile screens.

How do I calculate a percentage discount?

To find 20% off ₹1,500: press 1500 − 20 % =. The calculator computes 20% of 1,500 (= 300) and subtracts it, giving ₹1,200. This works for any percentage-of-base calculation.

What is the difference between basic and scientific calculator?

A basic calculator handles everyday arithmetic — the four operations, percentages, square roots and memory. A scientific calculator adds trigonometric functions (sin, cos, tan), logarithms (log, ln), factorials, constants (π, e), and more — tools needed for engineering, physics and advanced mathematics.