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

In connection with the Quarterly Report of Carreker Corporation (the Company) on Form 10-Q for the quarterly period ending October 31, 2004 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, John D. Carreker, Jr., Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that:

(1)The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2)The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/    JOHN D. CARREKER, JR.

John D. Carreker, Jr., Chief Executive Officer

Dated:    December 10, 2004