Quick guide
How to use this calculator
- Enter a finite decimal and decimal-place target.
- Compare all results row by row.
- Pay special attention to negative values and exact ties.
Calculation method
Direction and tie policy are separate choices
Directed modes choose toward zero, away from zero, floor, or ceiling. Nearest modes agree away from a tie and differ only when the discarded part is exactly half.
Worked example
Comparing −2.5 at zero places
Half-up gives −3, half-down gives −2, and half-even gives −2 because 2 is even.
−2.5 → {half up: −3, half down: −2, half even: −2}
Supported inputs
Precision and limits
Exact decimal input
Finite decimals use integer-scaled arithmetic, with no binary floating-point conversion.
Input boundary
Unless stated otherwise, use at most 200 digits total and 100 digits after the decimal marker.