Math
Rounding Calculator
Round a number to a decimal place or to the nearest ten, hundred, thousand — with floor and ceiling too.
Inputs
Rounding Calculator
Result
Rounded (half up)
123.46
- Floor
- 123.45
- Ceiling
- 123.46
- Original
- 123.4567
How it's calculated
Round half up: sign(x) · ⌊|x| · 10ᵖ + 0.5⌋ / 10ᵖ.
Common questions
What's the difference between round, floor, and ceiling?
Floor always drops down, ceiling always bumps up, round goes to whichever is nearest (with .5 going up here).
How do I round to a whole number?
Choose “Integer” under precision — that's rounding to 0 decimal places.
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