Exhibit 23.1

Independent Registered Public Accounting Firm’s Consent

We consent to the incorporation by reference in this Registration Statement of Nxt-ID, Inc. on Form S-3 of our report dated April 15, 2021 with respect to our audits of the consolidated financial statements of Nxt-ID, Inc. as of December 31, 2020 and 2019 and for each of the two years in the period ended December 31, 2020 appearing in the Annual Report on Form 10-K of Nxt-ID, Inc. for the year ended December 31, 2020. We also consent to the reference to our firm under the heading “Experts” in the Prospectus, which is part of this Registration Statement.

/s/ Marcum llp

Marcum llp

New York, NY

August 26, 2021