Rounding Calculator
Round any number to decimal places, whole numbers, or the nearest multiple.
What the Rounding Calculator does
Rounding replaces a number with a nearby simpler one. This calculator uses round-half-away-from-zero, the convention taught in schools and used in most financial reporting, and also shows ceiling, floor and truncation.
Formula
Round to n d.p.: ⌊x × 10ⁿ + 0.5⌋ ÷ 10ⁿRound to nearest m: round(x ÷ m) × m
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Number | number | Yes | — |
| Round to | one of 2 options | Yes | — |
| Decimal places | number | In some modes | Accepts 0 or more, up to 12. Shown Round to is Decimal places. |
| Multiple of | number | In some modes | Shown Round to is Nearest multiple. |
How to use it
- Choose Round to.
- Enter Number.
- Fill in the remaining inputs the form shows for your choice.
- Select Calculate.
Worked example
Round 3.14159 to two decimal places.
- Number
- 3.14159
- Decimal places
- 2
3.14, since the third decimal (1) is below 5.
Frequently asked questions
What is banker's rounding?
Round-half-to-even, which sends 2.5 to 2 and 3.5 to 4. It avoids the upward bias of always rounding halves up and is common in accounting software.
What is the difference between rounding and truncating?
Truncating always cuts digits off; rounding may increase the last kept digit.