# 64-bit real number: double, float, real

64-bit real number and his value range: from - 1.7 × 10 on 308 to +1.7 × 10 on 308 and it has 15 digit precision. if it is used to store integers the biggest integer what can store without rounding is 2 on 53. 64-bit real number is stored the following way: 1bit sign, 8bit exponent a 23bit mantissa.

## double

### Description

``double``
Used keywords: double
Note: In C like languages the data type size may be different depending on compiler and architecture, we show only one standard look.
Compatible programing languages:
Basic | Visual Basic .NET | FreeBASIC | C | Visual C++ .NET | C++ | C# | Java | Free Pascal | Object Pascal | Pascal | PHP

### Example

64-bit real number the possible of use:
``````double x = 3.14159265359;     // x = 3.14159265359
double y = 123456789;         // y = 123456789.0
y =(double)(x * y);          // y = 387850941.35821074``````

## float

### Description

`` float``
Used keywords: float
Compatible programing languages:
PHP

### PHP

64-bit real number the possible of use:
``````\$x= 3.14159265359;     // x = 3.14159265359
\$y= 123456789;         // y = 123456789.0
\$y =(double)(\$x * \$y);          // y = 387850941.35821074``````

## real

### Description

``real``
Used keywords: real
Compatible programing languages:
PHP

### PHP

64-bit real number the possible of use:
``````\$x= 3.14159265359;     // x = 3.14159265359
\$y= 123456789;         // y = 123456789.0
\$y =(double)(\$x * \$y);          // y = 387850941.35821074``````

You can find it in the following collections: real numbers | numbers | data types
64-bit real number in another programming language:
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