Subnormal number

This page describes subnormal numbers in general. For the details of IEEE subnormal and denormal numbers, see the IEEE section below.

In computer science, subnormal numbers are the subset of denormalized numbers (sometimes called denormals) that fill the underflow gap around zero in floating-point arithmetic. Any non-zero number with magnitude smaller than the smallest positive normal number is subnormal, while denormal can also refer to numbers outside that range.