The Rounding Calculator rounds a number to a chosen precision using many rounding methods, including half up, half down, half to even, ceiling and floor.
1234.5678 rounded = 1234.57
| Result | 1234.57 |
| Precision | Hundredths (2) |
| Mode | Round to the nearest (default) |
Rounding replaces a number with a simpler, shorter one that is close in value. It is used for money (two decimals), measurements, statistics and reporting, so that results are not falsely precise.
Round half up: 2.5 → 3, −2.5 → −2. Round half away from zero (the usual school method): 2.5 → 3, −2.5 → −3. Round half to even (banker's rounding): 2.5 → 2, 3.5 → 4, which avoids bias in large data sets. Ceiling always rounds up; floor always rounds down; truncation drops digits.
Positive precisions keep decimal places (hundredths = 2 decimals). Zero rounds to a whole number. Negative precisions round to tens, hundreds, thousands and so on: 1,234.5678 to hundreds is 1,200.
Worked example (defaults): 1,234.5678 to hundredths is 1,234.57.
Why does 2.675 sometimes round to 2.67 in software? Binary floating point cannot store it exactly.
What are significant figures? Digits that carry meaning, counted from the first non-zero digit.
Which method do banks use? Often round half to even.