Round any number to a set number of decimals, or to the nearest 10 or 100 — with round-up and round-down too.
Understanding the rounding calculation
Enter a number and choose how to round it: to whole numbers, a set number of decimals, or the nearest 10 or 100. The calculator also shows the round-up (ceiling) and round-down (floor) results.
Useful for estimates, money and tidy figures.
How to fill it in
- Enter the number.
- Choose how to round it.
- Read the rounded value plus round-up and round-down.
The calculation
round to nearest: multiply, round, divide back
round up = ceiling · round down = floor
Try it with these numbers
The calculator opens with a number of 3.14159, round to of 2 decimals. On those figures the rounded is 3.14. Underneath, Round up comes out at 3.15 and Round down at 3.14. Change any field and every figure updates as you type.
Questions people ask about this
How does rounding to decimals work?
Look at the next digit: 5 or more rounds up, less than 5 rounds down. The tool applies this for your chosen number of places.
What’s the difference between round, ceil and floor?
Round goes to the nearest; ceiling always goes up; floor always goes down.
How do I round to the nearest 100?
Divide by 100, round, then multiply back — the calculator has this as an option.