Exhibit 23.1

15590s3consent123118

CONSENT OF INDPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement on Form S‑8 of Cray Inc. of our reports dated February 12, 2019, relating to our audits of the consolidated financial statements of Cray Inc. and Subsidiaries (“the Company”) and the effectiveness of the Company’s internal control over financial reporting appearing in the Annual Report on Form 10‑K of Cray Inc. for the year ended December 31, 2018.

/s/ PETERSON SULLIVAN LLP

Seattle, Washington

August 9, 2019