How rounding works
Select decimal places or a named place value, then choose Round. This tool compares decimal digits as typed rather than depending on binary floating-point formatting. A halfway digit rounds away from zero: 12.5 becomes 13, while −12.5 becomes −13. Other rounding conventions can produce different tie results.
15.496 to two decimal places = 15.50. 1499 to the nearest hundred = 1500.
Scope and limits
Inputs may use ordinary decimal or scientific notation, up to 100 characters and exponent magnitude 30. Decimal-place choices range from 0 to 12. This is place-value rounding, not significant-figure rounding; use the Significant Figures Calculator for measured-value precision.
Privacy
Numbers are calculated in this browser tab. This page does not submit or persist your entries or place them in the URL.