is an option for NumberForm and related functions that gives the string to insert at breaks between digits.


  • NumberSeparator->"s" specifies that the string s should be inserted at every break between digits specified by DigitBlock.
  • NumberSeparator->{"sleft","sright"} specifies different strings to be used on the left and right of the decimal point.
  • The default setting is NumberSeparator->{","," "}.
  • NumberSeparator can also be used to specify the strings to assume for breaks between digits with Interpreter["Number",].


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Basic Examples  (3)

The default separator is a comma (,):

Use spaces instead:

Interpret numbers with a custom separator:

Scope  (3)

Use NumberSeparator with PaddedForm:




Specify different separators to the left and right of the number point:

The default number separators and number point:

Switch the role of periods and commas in the representation:

Introduced in 1988
Updated in 2014