Round a value to a chosen decimal place without hiding which digit controls the change. Its rounded number sits beside the working formula for a quick arithmetic check.
Rounding replaces a number with a nearby value at a stated place. The first discarded digit decides whether the retained digit stays or increases, while the place label explains the size of the permitted change. Another calculation beside Rounding is significant figures.
On this page, the displayed rounded number follows this definition rather than any similarly named measure.
Locate the requested place, underline its digit, and inspect the digit immediately to its right. Add one when that deciding digit is 5 or more, then replace discarded whole-number positions with zeros.
Rounding 47.3865 to two decimal places inspects the third decimal digit, 6. The hundredths digit rises from 8 to 9, producing 47.39.
Invoices, measurements, estimates, and published tables often need fewer digits than the working calculation. Keeping the unrounded source nearby prevents a presentation choice from silently becoming new data.
Rounding is different from truncation, which simply removes trailing digits. Negative place counts round tens, hundreds, or larger positions rather than digits after the decimal point.
Record the units for Rounding beside each source value; the reader must still confirm compatibility while performing rounding.
Treat each labeled field as part of the definition, not merely an empty box. The field assignment determines what the displayed rounded number describes. Convert measured values to compatible units first and retain their original precision until the final rounding choice.
Increasing the requested decimal places preserves more of the source number; decreasing it permits a larger step away from the original. Predict that movement before recalculating the rounded number; disagreement points to an input-role or sign issue.
Report the rounded number at a precision justified by the inputs. A long browser decimal is computational detail, not evidence that the source values were measured that accurately. When an exact symbolic form is conventional, keep it beside the rounded value so later work is not forced to reuse an early approximation.
Decimal-place rounding counts positions relative to the decimal point. Significant-figure rounding instead begins at the first nonzero digit. Here the requested quantity is specifically rounded number.
Keep the supplied inputs with the result, including any units and the final rounding place. The displayed formula then preserves how the rounded number was obtained.
Yes. Minus one rounds to tens, minus two to hundreds, and so on.
This page uses half-away-from-zero rounding, so 2.5 becomes 3 and −2.5 becomes −3.
Usually no; carry working precision and round the final reported value.