The rounding rule
Look at the digit just to the right of the place you are rounding to. If it is 5 or more, round up; if it is 4 or less, keep the digit and drop the rest. 3.14159 to two decimals: the next digit is 1, so 3.14.
Significant figures
Significant figures count from the first non-zero digit. 0.004567 to 2 significant figures is 0.0046; 45,678 to 2 significant figures is 46,000.
Round half to even
Banker’s rounding sends exact halves to the nearest even digit (2.5 → 2, 3.5 → 4), which avoids a small upward bias in large sums. Spreadsheets and some programming languages use it.
The usual rule
Look at the digit just after the place you’re rounding to. If it’s 5 or more, round up; if it’s 4 or less, leave the digit as it is. 3.46 to one decimal place is 3.5; 3.44 is 3.4.
Decimal places vs significant figures
Decimal places count digits after the point; significant figures count digits from the first non-zero digit. 0.004567 to two decimal places is 0.00, but to two significant figures it is 0.0046.
Banker’s rounding
Some software and accounting systems round exact halves to the nearest even digit (2.5 → 2, 3.5 → 4) so rounding errors don’t pile up in one direction. Choose “half to even (banker’s)” in the calculator to match.
Rounding money
Prices and totals are rounded to the cent (two decimal places). Round only the final answer, not each step: rounding every line of a long calculation can leave the total a few cents off.
Related calculators
- Decimal to Fraction Converter: Decimals to fractions and back.
- Fraction Calculator: Add, subtract, multiply and divide fractions.
- Percentage Calculator: X% of Y, X is what % of Y, and more.
Questions people ask
What is 2.45 rounded to one decimal?
2.5 with standard rounding (half up). With banker’s rounding it is 2.4.
How do I round to the nearest thousand?
Look at the hundreds digit: 45,678 has a 6, so it rounds up to 46,000.
Formula checked October 2026 · How we calculate