QuickLinks -- Click here to rapidly navigate through this document

Exhibit 32.1

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        I, Barry Diller, certify, pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, 18 U.S.C. Section 1350, that, to my knowledge:

(1)

Amendment No. 2 on Form 10-K/A (the "Amendment") to the Annual Report on Form 10-K for the fiscal year ended December 31, 2007 of IAC/InterActiveCorp (together with the Amendment, the "Report") which this statement accompanies fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

(2)

the information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of IAC/InterActiveCorp.

Dated: June 27, 2008 /s/  BARRY DILLER Barry Diller
Chairman and Chief Executive Officer

QuickLinks

Exhibit 32.1

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002