Rounding Calculator

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Round any number to decimal places, significant figures or the nearest 10, 100, 1000 or custom step, with half up, half down or half to even rounding. Free and instant.

Rounded value –
Round down (floor) –
Round up (ceiling) –
Truncated –
Half up rounds .5 away from zero, half down rounds .5 toward zero, and half to even (banker's rounding) rounds .5 to the nearest even multiple.

About Rounding Calculator

The rounding calculator rounds any number three different ways: to a set number of decimal places, to a chosen count of significant figures, or to the nearest 10, 100, 1,000 or a custom step you define. Alongside the main result it also shows the floor, ceiling and truncated values.

You control how ties are handled. Half up rounds .5 away from zero, half down rounds .5 toward zero, and half to even — often called banker’s rounding — rounds .5 to the nearest even multiple, the method used in many accounting and scientific contexts.

Use it whenever a homework problem, invoice, lab report or spreadsheet needs a value rounded a specific way. Everything is computed live in your browser, free, with no button to press.

How to use Rounding Calculator

  1. Type the number you want to round.
  2. Choose the mode: decimal places, significant figures or nearest step.
  3. Set the precision — how many places or figures, or which step (10, 100, 1,000 or custom).
  4. Pick a rounding method: half up, half down or half to even.
  5. Compare the rounded value with the floor, ceiling and truncated results.

Frequently asked questions

Decimal places count digits after the decimal point, so 3.14159 to 2 places is 3.14. Significant figures count all meaningful digits from the first nonzero one, so 0.004523 to 2 sig figs is 0.0045.

When a value sits exactly halfway, half to even rounds it to the nearest even multiple: 2.5 becomes 2 and 3.5 becomes 4. Over many operations this avoids the upward bias of always rounding halves up.

Truncation simply drops the extra digits, moving toward zero, while floor always moves toward negative infinity. For positive numbers they match; for −2.7 the truncated value is −2 but the floor is −3.

Yes. Choose the nearest mode, select Custom and enter any step, such as 25 for quarter-hundreds or 0.05 for cash rounding used in some countries.

Most spreadsheets round halves up by default. This rounding calculator lets you pick the tie-breaking rule explicitly, so match the method to the convention your class or workplace uses.
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