Rounding Calculator
Round a number to any place value, from millions down to six decimal places. Choose the place and the rounding method, and see the rounded number together with the nearest values below and above it. It works on the exact digits you type, so halves always round the way you expect.
- Nearest value below
- 3.14
- Nearest value above
- 3.15
Saved setups
Save a set of inputs you reuse — your usual rate, your loan, your room sizes — and load it back in one tap.
Your recent calculations
Results you calculate here are kept on this device so you can come back to them.
Formula
How to use it
- Type the number.
- Choose the place to round to — nearest ten, whole number, hundredth and so on.
- Leave the method on standard rounding unless you need banker’s rounding, ceiling, floor or truncation.
- Read the rounded number.
Worked examples
3.14159 to two decimal places
- Rounded number
- 3.14
- Nearest value below
- 3.14
- Nearest value above
- 3.15
2.675 to the nearest hundredth (a value many calculators get wrong)
- Rounded number
- 2.68
1,847 to the nearest hundred
- Rounded number
- 1800
- Nearest value below
- 1800
- Nearest value above
- 1900
8.5 to a whole number with banker’s rounding
- Rounded number
- 8
The rounding methods
Half away from zero is the rule taught in school: 2.5 becomes 3 and −2.5 becomes −3. Half to even, or banker’s rounding, sends an exact half to the nearest even digit — 2.5 becomes 2 and 3.5 becomes 4 — so that rounding errors cancel out over many values; it is the default in the IEEE 754 floating-point standard.
Ceiling always moves toward the larger value and floor toward the smaller one, so −2.7 has a ceiling of −2 and a floor of −3. Truncating simply cuts the extra digits off: 2.79 becomes 2.7.
Why 2.675 trips up other calculators
Computers store most decimals in binary, where 2.675 is really 2.67499999999999982…, so many programs round it to 2.67. This calculator rounds the decimal digits themselves and gives 2.68.
Round once, from the original number. 2.449 to the nearest whole number is 2. Rounding in stages — 2.449 to 2.45, then to 2.5, then to 3 — gives the wrong answer.
Questions people ask
What is 3.14159 rounded to two decimal places?
3.14. The third decimal is 1, which is less than 5, so the 4 stays.
What is 1,847 rounded to the nearest hundred?
1,800. The tens digit is 4, so the hundreds digit stays at 8.
What is 2.5 rounded to the nearest whole number?
3 with standard rounding. With banker’s rounding (half to even) it is 2.
What is 0.065 rounded to the nearest hundredth?
0.07 with standard rounding, because the digit after the hundredths place is 5.