Creating a solution > About choosing a field type > About number fields
About number fields
Use number fields to store numeric values.
Use number fields to store:
numbers that need to be sorted in numeric order. FileMaker Pro indexes the first 400 significant digits (numbers, decimal points, or signs) of the field, ignoring letters and other symbols.
numbers used in calculation formulas or summary fields. By default, FileMaker Pro performs fixed-point math with a minimum of 16 digits of precision to the right of the decimal point. Use the SetPrecision function to further expand the precision of this number.
values that are a combination of numbers, letters, and special characters that still need to use the numbers in calculations and sorting (for example, $400 or best offer).
Use text fields instead of number fields to store postal codes, phone numbers, and other values with leading zeroes or characters like hyphens or parentheses.
The characters displayed for the decimal separator and thousands separator depend on the system formats set for the database file, and the display format for the field. For information on changing the display format for a field (for example, 2.45 or $2.45), see Specifying formats for fields containing numbers.
Related topics 
Defining and changing fields
Specifying formats for fields containing numbers