Exhibit 23.1
CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
We have issued our reports dated February 21, 2020, with respect to the consolidated financial statements, schedule and internal control over financial reporting of Qualys, Inc. included in the Annual Report on Form10-K for the year ended December 31, 2019, which are incorporated by reference in this Registration Statement. We consent to the incorporation by reference of the aforementioned reports in this Registration Statement.
| /s/ Grant Thornton LLP |
| San Jose, California |
| February 21, 2020 |
