Basic Calculator

How the Basic Calculator Works

The Basic Calculator is designed to feel like a simple handheld calculator, but in your browser. You tap number and operator buttons to build a single expression, then press = to evaluate it. Behind the scenes, the calculator parses the expression, applies standard order of operations, and returns a neatly formatted result that you can immediately reuse for the next calculation.

Expression-Based Input Instead of One-Step Math

Instead of computing every step separately, this calculator lets you type out the entire expression in one go:

• Build expressions such as 7 + 8 − 3 × 2 and evaluate them with a single tap on =.
• Use decimals like 12.75 or 0.08 to keep your calculations precise.
• Insert the percent key to convert 10 into 10% (0.1) inside the expression.

This approach makes it easier to check homework or copy expressions from worksheets and bills without changing how you naturally write the math.

Order of Operations & Percent Handling

Internally, the Basic Calculator evaluates expressions according to the same priority rules you learn in school:

• Multiplication and division are evaluated before addition and subtraction.
• Operators at the same level are handled from left to right.

The percent key is treated in a simple, predictable way: it divides the number immediately before it by 100. For example, 10 % becomes 0.1, and 50 × 10 % becomes 5. This keeps the logic easy to understand and consistent across different inputs.

Display, Rounding & Error Recovery

The display shows your expression as you build it and then shows the result once you press =. To keep results readable:

• Very small rounding artifacts are trimmed so 1.999999999999 displays as 2.
• Trailing zeros after the decimal point are shortened when possible.

If something goes wrong—such as an incomplete expression—the calculator clears out and resets to 0 instead of showing a confusing error value. You can always start fresh with AC.

What This Calculator Does Not Do

To stay fast and easy to use, this Basic Calculator intentionally leaves out some advanced features:

• No memory keys (MC, MR, M+, M−).
• No square roots, powers, scientific notation buttons, or π.
• No running tape or history of previous calculations.
• No financial or statistical functions.

It focuses purely on everyday arithmetic: addition, subtraction, multiplication, division, decimals, and percentages—all on one clean, responsive page that's easy to use on both desktop and mobile.