Rounding Calculator
This rounding calculator rounds any number to whatever place you need: the nearest whole, ten, hundred, tenth, hundredth, a set number of decimal places, or significant figures. Type a number, pick a place, and you'll see the rounded result, a number line showing which way it goes, and the steps. It's the quick way to round prices, measurements, and answers without second-guessing the rule.
- Any place value
- Decimals and sig figs
- Nearest cent
- Number-line view
- Steps shown
Last updated June 16, 2026 5 or more rounds up Reviewed by the Calcowa math team
Enter a number to round.
3.47 to the nearest tenth: next digit is 7, so round up to 3.5
How to round a number
Rounding replaces a number with a nearby, simpler one to a chosen place. The rule is short: find the digit in the place you're keeping, then look at the digit just to its right. If that next digit is 5 or more, round up; if it's 4 or less, round down and leave your digit alone. Everything after the rounding place becomes zero or drops off, and that's all there is to it.
Rounding 3.47 to the nearest tenth
Here's the rule in action:
- 1
Find the placeThe tenths digit in 3.47 is the 4.
- 2
Check the next digitThe digit to its right is 7.
- 3
Round7 is 5 or more, so the 4 rounds up to 5, giving 3.5.
Decimal places, cents, and significant figures
It's the same rule at every place. Rounding to two decimal places is the same as the nearest hundredth, which is also how you round money to the nearest cent, so $4.005 becomes $4.01. Significant figures count from the first nonzero digit instead of from the decimal point, so 0.04519 to two significant figures is 0.045. Pick the decimal-places or significant-figures option above and a small box'll appear for how many you want. For the sig-fig rules and a digit-by-digit count, the significant figures calculator goes deeper.
Round half up vs round half even
When the deciding digit is exactly 5 with nothing after it, there's a choice. Round half up, the version taught in school and used here, always sends it upward, so 2.5 becomes 3. Round half even, common in statistics and some accounting, rounds to the nearest even number instead, turning 2.5 into 2 and 3.5 into 4 to avoid a slight upward bias over many values. For everyday rounding, half up is what you want, and that's what this tool uses.
Rounding examples
| Round to | Number | Result |
|---|---|---|
| Nearest whole | 7.62 | 8 |
| Nearest tenth | 3.47 | 3.5 |
| Nearest hundredth | 2.718 | 2.72 |
| Nearest ten | 63 | 60 |
| Nearest hundred | 349 | 300 |
| Nearest cent | 4.005 | 4.01 |
Frequently asked questions
Why does 5 round up?
It's a simple, consistent rule: a deciding digit of 5 or more is closer to the next number up, or tied, so the convention sends it up. Using one fixed rule keeps everyone's rounding in agreement, which matters more than the rare tie.
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, round down and leave the rounding digit as it is. To round 3.47 to the nearest tenth, the next digit is 7, so you round up to 3.5.
Keep two digits after the decimal point and look at the third. If that third digit is 5 or more, bump the hundredths digit up by one; otherwise leave it. So 2.718 rounds to 2.72, because the next digit, 8, is 5 or more, so it's that mechanical.
Keep one digit after the decimal point and check the next one. For 3.47, the hundredths digit is 7, which is 5 or more, so the tenths digit rounds up and you get 3.5. The number line above shows which side it's nearer.
Count significant figures from the first nonzero digit, then round at that position using the next digit. Rounding 0.04519 to 2 significant figures keeps the 4 and 5, looks at the 1, and gives 0.045. The calculator does this when you've chosen significant figures.
When the deciding digit is exactly 5 with nothing after it, round half up always goes up, so 2.5 becomes 3. Round half even, used in some science and finance, rounds to the nearest even number, so 2.5 becomes 2 and 3.5 becomes 4. This calculator uses round half up, the version you'll have learned in school.
Rounding to the nearest cent is just rounding to two decimal places, since a cent is one hundredth of a dollar. So $4.005 rounds to $4.01. Choose nearest hundredth or nearest cent above and you'll get the same answer.
Related calculators
More number tools.
Round or count sig figs.
Average calculatorMean, median, mode, range.
All math calculatorsPercent, fractions, averages, more.
Rounding a number?
Type a number and pick a place above, or browse the full math hub.