Round Calculator
Rounding Calculator works out Rounded value and Rounded value (formatted) from Number to round, Decimal places and Place value. The default figures on this page give rounded value of 1,234.57; change any entry and the result, the working and the sources update together.
Your figures
Updates as you typeHow this is worked out
4 steps
- Rounding 1234.567 to 2 decimal places using "round half away from zero".
- The rounding step is 0.01, so the neighbours are 1234.56 and 1234.57.
- 1234.567 / 0.01 = 123456.7, which the rule sends to 123457.
- 123457 x 0.01 = 1234.57
Its 7 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
2 sources
What the Rounding Calculator calculates
Rounds a number to a chosen number of decimal places, a named place value, the nearest multiple, or a number of significant figures, under any of the standard tie-breaking rules including half away from zero and banker's half-to-even, and estimates a sum by rounding every addend to a place value before adding them.
How to use this Rounding Calculator
Enter Number to round, Decimal places, Place value and Significant figures. Rounded value updates as you type, and “Use a worked example” loads checked figures you can adjust. Change one figure at a time to see what drives the result.
How the result is worked out
Open “How this is worked out” beside the result for the step-by-step calculation behind Rounded value, Rounded value (formatted) and Rounded minus original.
The method follows IEEE Std 754-2019, Standard for Floating-Point Arithmetic, §4.3 Rounding-direction attributes (roundTiesToEven, roundTowardZero, roundTowardPositive, roundTowardNegative) and NIST Special Publication 811, Guide for the Use of the International System of Units, Appendix B.7 "Rounding converted numerical values".
2.5 to a whole number, half away from zero example
With Number to round: 2.5, Round to: decimals, Decimal places: 0, Tie-breaking / direction rule: half-up, the calculator returns Rounded value: 3, Rounded minus original: 0.5. This example is checked against an independent source in the test suite.
What you can compare
Change one input at a time to see how it affects Rounded value, Rounded value (formatted) and Rounded minus original. The inputs you can vary are Number to round, Decimal places, Place value, Significant figures, Numbers to add and Tie-breaking / direction rule.
Results are general information, not financial, tax, legal, medical or engineering advice. Check any decision that matters with a qualified professional.
See something wrong? Report a problem with this calculator
Frequently asked questions
How can I round a number?
Rounds a number to a chosen number of decimal places, a named place value, the nearest multiple, or a number of significant figures. Open “How this is worked out” beside the result to see each step for your own figures.
How do I round a number to the nearest number?
It needs Number to round, Decimal places, Place value, Significant figures, Numbers to add and Tie-breaking / direction rule. Nothing else is required, and the figures stay in your browser.
Is 7 rounded to 5 or 10?
Rounds a number to a chosen number of decimal places, a named place value, the nearest multiple, or a number of significant figures. On the figures this page opens with — number to round 2.5 — the rounded value is 1,234.57. Put your own figures in their place and the working updates beside the result.
How do I round a number to the nearest dollar?
The result gives Rounded value, Rounded value (formatted), Rounded minus original, Rounded toward -infinity, Rounded toward +infinity and Rounding step (place value), each labelled with its unit so the figure can be read on its own.
What information do I need for the Rounding Calculator?
You need Number to round, Decimal places, Place value, Significant figures, Numbers to add and Tie-breaking / direction rule. The page opens with default figures that give rounded value of 1,234.57, so you can see the scale before entering your own.
What does this Rounding Calculator show?
It shows Rounded value, Rounded value (formatted), Rounded minus original, Rounded toward -infinity, Rounded toward +infinity, Rounding step (place value), Rule applied and Estimated sum (rounded numbers added), with the working and any warnings for your entries.