Round Nearest Thousandth Calculator
Round to nearest thousandth calculator works out Rounded value and Rounded value (formatted) from Number to round and Tie-breaking / direction rule. The default figures on this page give rounded value of 1,234.567; 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 3 decimal places using "round half away from zero".
- The rounding step is 0.001, so the neighbours are 1234.567 and 1234.567.
- 1234.567 / 0.001 = 1234567, which the rule sends to 1234567.
- 1234567 x 0.001 = 1234.567
Its 7 worked examples are re-run on every release, last on 15 September 2026. What changed
Sources and references
2 sources
What the round to nearest thousandth 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 round to nearest thousandth calculator
Enter Number to round and Tie-breaking / direction rule. Rounded value updates as you type. 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".
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 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 do I round to the nearest thousandth?
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 495 to the nearest 1000?
It needs Number to round and Tie-breaking / direction rule. Nothing else is required, and the figures stay in your browser.
What is 1324 to the nearest 1000?
Rounds a number to a chosen number of decimal places, a named place value, the nearest multiple, or a number of significant figures. On this page it is computed from Number to round and Tie-breaking / direction rule and shown as Rounded value, Rounded value (formatted) and Rounded minus original.
What is 1.2977 rounded to the nearest thousandth?
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.
How to round to nearest thousandth?
The page opens with worked default figures: rounded value of 1,234.567. Replace them with your own and every figure updates as you type.
What is 0.1234 rounded to the nearest thousandth?
The method comes from 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", listed in full under Sources so the figures can be checked against the original.