Duolingo

Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers. On August 10, 2026, the Board of Directors (the Board ) of Duolingo, Inc. (the Company ) increased the size of the Board from nine to ten directors and appointed Sallie Krawcheck to serve as a Class I director on the Company s Board and as a member of its Audit, Risk and Compliance Committee ("Audit Committee"), in each case, effective immediately. Ms. Krawcheck will serve for a term expiring at the Company s annual meeting of stockholders to be held in 2028 and until her successor is duly elected and qualified or until her earlier death, resignation, disqualification or removal. Ms. Krawcheck is eligible to participate in the Company s Non-Employee Director Compensation Program. Her director compensation includes: (i) an annual cash retainer of $45,000 for serving on the Board, paid quarterly in arrears (prorated based on her service during the 2026 fiscal year); (ii) an annual cash retainer of $10,000 for serving on the Audit Committee, paid quarterly in arrears (prorated based on her service during the 2026 fiscal year), (iii) an initial award of restricted stock units ( RSUs ) equal to $450,000 divided by the closing price of the Company s Class A common stock on the date Ms. Krawcheck commences service on the Board (the Initial RSU Award ) which will vest as to 50% of the Initial RSU Award on the first anniversary of the grant date, 25% of the Initial RSU Award on the second anniversary of the grant date, and the remaining 25% on the third anniversary of the grant date, subject to her continued service on the Board through each such vesting date; (iv) a prorated annual RSU award equal to $180,000 divided by the closing price of the Company s Class A common stock on the date Ms. Krawcheck commences service on the Board which will vest on the earlier of the first anniversary of the grant date or immediately prior to the next annual meeting of the Company s stockholders following the grant date, in either case, subject to her continued service on the Board through such vesting date and (v) an annual RSU award granted on the date of the Company s annual meeting of stockholders, provided she has served on the Board for at least six months prior to such annual meeting and will continue serving following such meeting, in an amount equal to $215,000 divided by the closing price of the Company s Class A common stock on the grant date which will vest in full on the earlier of the first anniversary of the grant date or immediately prior to the next annual meeting of the Company s stockholders following the grant date, in either case, subject to her continued service on the Board through such vesting date. Ms. Krawcheck is expected to enter into the Company s standard form indemnification agreement in the form filed as Exhibit 10.12 to the Company s Registration Statement on Form S-1/A (File No. 333-257483) filed with the Securities and Exchange Commission on July 19, 2021.

Item 7.01 Regulation FD Disclosure. On August 10, 2026, the Company issued a press release announcing the appointment of Ms. Krawcheck. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated in this

Item 9.01 Financial Statements and Exhibits. (d) Exhibits. Exhibit No. Description 99.1 Press Release dated August 10, 2026 104 Cover Page Interactive Data File (embedded within the inline XBRL document) SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. DUOLINGO, INC. Date: August 10, 2026 By: /s/ Gillian Munson Gillian Munson Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)