# REAL(4) Constants

A single-precision REAL constant occupies four bytes of memory. The number of digits is unlimited, but typically only the leftmost seven digits are significant.

IEEE* IEEE binary32 format is used.

Note that compiler option real-size can affect REAL data.

## Examples

Valid REAL(4) Constants
`3.14159`
`3.14159_4`
`621712._4`
`-.00127`
`+5.0E3`
`2E-3_4`

Invalid REAL(4) Constants
`1,234,567.` | Commas not allowed.
`325E-47` | Too small for REAL; this is a valid DOUBLE PRECISION constant.
`-47.E47` | Too large for REAL; this is a valid DOUBLE PRECISION constant.
`625._6` | 6 is not a valid kind for reals.
`100` | Decimal point is missing; this is a valid integer constant.
`$25.00` | Special character not allowed.

Parent topic: Real Data Types

## See Also

General Rules for Real Constants
real-size compiler option

Compiler Reference > Data and I/O section: Data Representation