Rounding Calculator
Round numbers to decimals, significant figures or the nearest 10/100/1000.
Round to a number of decimal places or significant figures, or to the nearest 10/100/1000 — with round, floor (down) or ceil (up) modes. Runs in your browser.
Round a number however you need: to a chosen number of decimal places, to significant figures, or to the nearest 10, 100 or 1000. Switch between round-to-nearest, round down (floor) and round up (ceiling). Useful for reports, estimates and homework. Runs in your browser.
How to use the Rounding Calculator
- Enter a number and pick round, floor or ceil.
- Choose decimal places or significant figures with the sliders.
- Read the rounded value, including to the nearest 10/100/1000.
Frequently asked questions
What are significant figures?
The digits that carry meaning in a number's precision, starting from the first non-zero digit. Rounding 3.14159 to 3 significant figures gives 3.14.
What's the difference between floor and ceil?
Floor always rounds down toward negative infinity; ceil always rounds up toward positive infinity; round goes to the nearest, with .5 rounding up.