How Rounding Works
Rounding replaces a number with a simpler nearby value. The standard rule: identify the rounding place, look one digit to its right, and round up if that digit is 5–9, down if it is 0–4. Everything past the rounding place is then dropped (for decimals) or replaced with zeros (for tens, hundreds and larger places).
Round 7,846 to the nearest hundred: the hundreds digit is 8, the digit to its right is 4, so it stays — the answer is 7,800. To the nearest ten instead, the 4 is followed by 6, which rounds it up: 7,850.
One Number, Every Rounding
| π = 3.14159265… | Result |
|---|---|
| Nearest whole number | 3 |
| Nearest tenth | 3.1 |
| Nearest hundredth | 3.14 |
| Nearest thousandth | 3.142 |
| 4 decimal places | 3.1416 |
Note how the thousandths result ends in 2 but the 4-decimal result ends in 16 — each rounding looks only at the next digit, so results at different precisions can differ in their final digit. Always round once, from the original number.
Frequently Asked Questions
What is the standard rounding rule?
Look at the digit immediately to the right of the place you are rounding to. If it is 5 or more, round up; if it is 4 or less, round down. Rounding 3.746 to the nearest tenth looks at the 4, so the answer is 3.7.
How do I round to the nearest tenth, hundredth or thousandth?
The tenth is the first decimal place, the hundredth the second, the thousandth the third. Rounding 2.9184: nearest tenth 2.9, nearest hundredth 2.92, nearest thousandth 2.918.
How does rounding negative numbers work?
The same digit rule applies to the absolute value: −2.35 rounded to the nearest tenth is −2.4 under the “round half away from zero” convention this calculator uses, which is what is taught in schools.
What is banker’s rounding?
A convention where exact halves round to the nearest even digit (2.5 → 2, 3.5 → 4) to avoid systematic bias in large data sets. Spreadsheets and school math use standard rounding instead, which is what this calculator does.
Cite This Calculator
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The CalculatorsGuide Editorial Team. (2026). Rounding Calculator. CalculatorsGuide. Retrieved from https://www.calculatorsguide.com/math/rounding-calculator/