Double-precision Floating-point Format

Double-precision Floating-point Format

In computing, double precision is a computer number format that occupies two adjacent storage locations in computer memory. A double-precision number, sometimes simply called a double, may be defined to be an integer, fixed point, or floating point (in which case it is often referred to as FP64).

Modern computers with 32-bit storage locations use two memory locations to store a 64-bit double-precision number (a single storage location can hold a single-precision number). Double-precision floating-point is an IEEE 754 standard for encoding binary or decimal floating-point numbers in 64 bits (8 bytes).

Floating-point precisions
IEEE 754
  • 16-bit: Half (binary16)
  • 32-bit: Single (binary32), decimal32
  • 64-bit: Double (binary64), decimal64
  • 128-bit: Quadruple (binary128), decimal128
  • Extended precision formats
Other
  • Minifloat
  • Arbitrary precision

Read more about Double-precision Floating-point Format:  IEEE 754 Double-precision Binary Floating-point Format: Binary64