Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement on Form S-3 of our reports dated February 18, 2022 relating to the financial statements of Roku, Inc. and the effectiveness of Roku, Inc.’s internal control over financial reporting, appearing in the Annual Report on Form 10-K of Roku, Inc. for the year ended December 31, 2021. We also consent to the reference to us under the heading “Experts” in such Registration Statement.

/s/ DELOITTE & TOUCHE LLP

San Jose, California

March 4, 2022