As of Version 6.0, $RandomState has been superseded by the scoping construct BlockRandom.


gives a representation of the internal state of the pseudorandom generator used by Random.


  • The value of $RandomState changes every time Random is called.
  • You can use s=$RandomState to explicitly save the value of $RandomState, and $RandomState=s to restore.
  • The value of $RandomState is always a long integer chosen from a certain large set of possibilities. You can assign $RandomState only to values in this set.
  • You can use Block[{$RandomState},expr] to localize the value of $RandomState during the evaluation of expr.

See Also



Introduced in 1996