Quick guide
How to use this calculator
- Enter a finite decimal.
- Read the greatest integer less than or equal to it.
- Notice that negative values move toward negative infinity.
Calculation method
Floor points downward
An integer remains unchanged. A positive fractional value discards its fraction; a negative fractional value moves to the next lower integer.
Worked example
Floor of a negative decimal
−2 is the greatest integer that is no larger than −1.2.
floor(−1.2) = −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.