Rounding Calculator

Inputs

Number

Round By

Decimal places

Rounding mode

Result

—

waiting…

Steps

Enter a number to begin.

What is a Rounding Calculator?

A rounding calculator is a simple online tool that helps you quickly adjust numbers to a chosen level of precision. Whether you need to round to 2 decimal places, 3 significant figures, or the nearest multiple, this calculator does the work instantly.

How to Use the Calculator

Enter your number (decimals and scientific notation supported).
Select how you want to round:

- Decimals – choose the number of decimal places.
- Significant Figures – round to 1–10 sig figs.
- Multiple – round to the nearest step (e.g., 0.05, 5, 100).
- Integer – round to the nearest whole number.

Pick a rounding mode: Half Up, Half Even (Banker’s), Half Away, Half Down, Truncate, Floor, or Ceil.
Click Calculate to get your result instantly.

Why Use This Tool?

✅ Handles large and small numbers, including scientific notation.
✅ Offers different rounding rules for maths, science, and finance.
✅ Works instantly in your browser—no downloads required.
✅ Provides step-by-step explanations so you understand how the result was obtained.

Common Uses

Rounding currency values (e.g., $123.456 → $123.46).
Simplifying measurements in science and engineering.
Formatting numbers in statistics and reports.
Rounding grades, scores, or percentages.

Examples

12.3456 → 2 decimal places (Half Up) = 12.35
–12.5 → nearest integer (Half Even) = –12
0.000987 → 2 significant figures = 0.00099
123 → nearest multiple of 0.05 = 123.00

FAQs – Countdown Timer

Q: Can this calculator round negative numbers?
Yes. It supports negative values and applies rounding rules consistently.

Q: What’s the difference between Half Up and Half Even rounding?

Half Up always rounds 0.5 up.
Half Even (Banker’s rounding) rounds 0.5 to the nearest even digit to reduce bias.

Q: Can I copy or share the result?
Yes. Use the Copy button to copy results, or the Share button to generate a URL with your settings.

Q: Does it support scientific notation (e.g., 1.23e-4)?
Absolutely. Enter numbers in E-notation and they’ll be parsed correctly.