Rounding Calculator
Round a number to the nearest 10, 100, 1000, or to a set number of decimal places. Choose round-half-up or round-half-to-even (banker's rounding).
Rounded result
3.14
Round half up
3.14
Round half to even
3.14
The two methods only differ when the value is exactly halfway. Half-up always rounds a trailing 5 upward; banker's rounding sends it to the nearest even digit to avoid bias over many values.
Frequently Asked Questions
How do I round to the nearest 10 or 100?
Look at the digit in the place just below the one you are rounding to. If it is 5 or more, round up; otherwise round down. To round 1234 to the nearest 100, the tens digit is 3, so it rounds down to 1200.
How do I round to a number of decimal places?
Keep that many digits after the decimal point and use the next digit to decide whether to round up. Rounding 3.14159 to two decimal places gives 3.14, and to three places gives 3.142.
What is round half up?
Round half up (the common school method) rounds a trailing 5 upward: 2.5 becomes 3 and 3.5 becomes 4. It is simple but introduces a slight upward bias when you round many numbers.
What is round half to even (banker's rounding)?
Round half to even rounds a trailing 5 to the nearest even digit: 2.5 becomes 2 and 3.5 becomes 4. By splitting ties evenly it removes the upward bias, which is why banks and many standards use it.
Why do round half up and banker's rounding sometimes differ?
They only differ when the value is exactly halfway. 0.5 rounds to 1 with half-up but to 0 with banker's rounding, and 1.5 rounds to 2 in both. For any non-tie value the two methods give the same result.