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                                                                    EXHIBIT 23.1

                          Independent Auditor's Consent

         We consent to the incorporation of our report dated April 28, 1998, on
the financial statements of InterExchange, Inc. and Combined Affiliates as of
December 31, 1997, 1996 and 1995 and for the years the ended, which is included
in Form 8-K/A filed by IDT Corporation filed May 26, 1998.



                                        /s/ Amper, Politziner & Mattia P.A.



May 26, 1998
Edison, New Jersey


