Rounding Calculator

This rounding calculator rounds a number to decimal places, tens, hundreds or any multiple such as 0.05. The number 2.665 rounded to two places gives 2.67 with the usual half-up rule but 2.66 with round half to even – all four rules are shown side by side.

Example: Number to round 2.665 · Round to: Decimal places, tens, hundreds … · Place: 2 decimal places (hundredths) · Rounding rule: Half up (5 rounds up) → Rounded value: 2.67. Source: Wikipedia – Rounding (round half away from zero, round half to even, directed rounding). Updated: 30 September 2026.

How it is calculated

How the rounding calculator works

Enter a number, pick the place and the rule, and the result appears at once. The calculator uses exact decimal arithmetic instead of floating point, so 2.675 really rounds to 2.68 even though many programs return 2.67.

The four rounding rules

Half up: if the digit after the rounding place is 5 or more, the number goes up, otherwise down. 2.665 → 2.67; −2.5 → −3.
Half to even: an exact tie goes to the nearest even digit. 2.665 → 2.66; 2.675 → 2.68; −2.5 → −2. This spreads rounding errors evenly and is the default in IEEE 754.
Round down: extra digits are cut off, toward 0 for negative numbers.
Round up: as soon as anything follows the place, the number goes up, away from 0 for negative numbers.

Rounding to tens, hundreds or 5 cents

A negative place rounds before the decimal point: 1,234 to the nearest hundred is 1,200. With “A multiple” you can round to any step, for example 2.52 to 0.05 = 2.50. That is how cash totals are rounded to 5 cents in countries such as the Netherlands, Finland and Belgium.

Honest limits

Rounding always introduces a small error: adding several rounded intermediate results can differ from the exact total. Round only at the end. For tax or accounting, the rounding rules of the relevant regulation apply, not just these four.

Frequently asked questions

How do I round to 2 decimal places?

Look at the third decimal: 5 or more rounds up, less rounds down. 3.14159 becomes 3.14 and 2.675 becomes 2.68.

How do I round to the nearest whole number?

Choose “Whole number”: the first decimal decides, so 7.5 becomes 8 and 7.4 becomes 7.

What does round half to even mean?

When a value is exactly halfway between two numbers it goes to the even one: 2.5 → 2 and 3.5 → 4. Over many values the errors cancel out.

How do I round to the nearest 5 cents?

Choose “A multiple” and enter 0.05: 2.52 becomes 2.50 and 2.53 becomes 2.55.

How do I round negative numbers?

With half up the size is rounded and the sign stays: −2.5 → −3. “Round up” and “Round down” mean away from and toward 0, not toward plus or minus infinity.

Sources and legal basis

As of: 30 September 2026