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**Single-precision floating-point format** (sometimes called **FP32** or **float32**) is a computer number format, usually occupying 32 bits in computer memory; it represents a wide dynamic range of numeric values by using a floating radix point.

A floating-point variable can represent a wider range of numbers than a fixed-point variable of the same bit width at the cost of precision. A signed 32-bit integer variable has a maximum value of 2^{31} − 1 = 2,147,483,647, whereas an IEEE 754 32-bit base-2 floating-point variable has a maximum value of (2 − 2^{−23}) × 2^{127} ≈ 3.4028235 × 10^{38}. All integers with 7 or fewer decimal digits, and any 2^{n} for a whole number −149 ≤ *n* ≤ 127, can be converted exactly into an IEEE 754 single-precision floating-point value.

In the IEEE 754-2008 standard, the 32-bit base-2 format is officially referred to as **binary32**; it was called **single** in IEEE 754-1985. IEEE 754 specifies additional floating-point types, such as 64-bit base-2 *double precision* and, more recently, base-10 representations.

One of the first programming languages to provide single- and double-precision floating-point data types was Fortran. Before the widespread adoption of IEEE 754-1985, the representation and properties of floating-point data types depended on the computer manufacturer and computer model, and upon decisions made by programming-language designers. E.g., GW-BASIC's single-precision data type was the 32-bit MBF floating-point format.

Single precision is termed *REAL* in Fortran,^{[1]} *SINGLE-FLOAT* in Common Lisp,^{[2]} *float* in C, C++, C#, Java,^{[3]} *Float* in Haskell^{[4]} and Swift,^{[5]} and *Single* in Object Pascal (Delphi), Visual Basic, and MATLAB. However, *float* in Python, Ruby, PHP, and OCaml and *single* in versions of Octave before 3.2 refer to double-precision numbers. In most implementations of PostScript, and some embedded systems, the only supported precision is single.

Floating-point formats |
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IEEE 754 |

Other |

**^**"REAL Statement".*scc.ustc.edu.cn*. Archived from the original on 2021-02-24. Retrieved 2013-02-28.**^**"CLHS: Type SHORT-FLOAT, SINGLE-FLOAT, DOUBLE-FLOAT..."**^**"Primitive Data Types".*Java Documentation*.**^**"6 Predefined Types and Classes".*haskell.org*. 20 July 2010.**^**"Float".*Apple Developer Documentation*.

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