Approximate number data types for use with floating point numeric data. Floating point data is approximate; not all values in the data type range can be precisely represented.

**float **[ **( ***n ***) **]

Is a floating point number data from - 1.79E + 308 through 1.79E + 308. *n* is the number of bits used to store the mantissa of the **float** number in scientific notation and thus dictates the precision and storage size. *n* must be a value from **1** through **53**.

n is |
Precision | Storage size |
---|---|---|

1-24 |
7 digits | 4 bytes |

25-53 |
15 digits | 8 bytes |

The Microsoft® SQL Server™ **float**[**(***n***)**] data type conforms to the SQL-92 standard for all values of *n* from **1** to **53**. The synonym for **double precision** is **float(53)**.

**real**

Floating point number data from ?3.40E + 38 through 3.40E + 38. Storage size is 4 bytes. In SQL Server, the synonym for real is **float(24)**.