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duol-202602260001562088false00015620882026-02-262026-02-27

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K/A

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 26, 2026

Duolingo, Inc. (Exact name of registrant as specified in its charter)

Delaware001-4065345-3055872 (State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification Number)

5900 Penn Avenue Pittsburgh, Pennsylvania 15206 (Address of principal executive offices) (Zip Code) Registrant’s telephone number, including area code: (412) 567-6602

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s) Name of each exchange on which registered Class A common stock, $0.0001 par value per shareDUOLThe Nasdaq Stock Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company  ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

EXPLANATORY NOTE

On February 26, 2026, Duolingo, Inc. (the “Company”) furnished a Current Report on Form 8-K (the “Original Form 8-K”) appending as Exhibits 99.1 and 99.2, respectively, the Company’s press release (the “Original Press Release) and shareholder letter (the “Original Shareholder Letter”), announcing the financial results of the Company for the three and twelve months ended December 31, 2025. This amendment to the Original Form 8-K is being furnished solely to correct a typographical error on page 4 of the Original Shareholder Letter, regarding the Company’s net income for the year ended December 31, 2025, which was elsewhere correctly stated as $414.1 million. Except for the language on page 4 of the Original Shareholder Letter regarding the Company’s net income for the year ended December 31, 2025, all information set forth in the Original Form 8-K, the Original Press Release and original Shareholder Letter remains unchanged.

Item 2.02 Results of Operations and Financial Condition

On February 26, 2026, the Company issued the Original Shareholder Letter. A copy of the Original Shareholder Letter, as corrected, is attached hereto as Exhibit 99.1 and incorporated herein by reference.

Item 9.01 Financial Statements and Exhibits (d) Exhibits.

Exhibit No.Description

99.1Shareholder Letter dated February 26, 2026, as corrected

104Cover 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: February 27, 2026 By:/s/ Gillian Munson

Gillian Munson Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)

duol-202602260001562088false00015620882026-02-262026-02-26

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 26, 2026

Duolingo, Inc. (Exact name of registrant as specified in its charter)

Delaware001-4065345-3055872 (State or other jurisdiction of incorporation) (Commission File Number) (IRS Employer Identification Number)

5900 Penn Avenue Pittsburgh, Pennsylvania 15206 (Address of principal executive offices) (Zip Code) Registrant’s telephone number, including area code: (412) 567-6602

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s) Name of each exchange on which registered Class A common stock, $0.0001 par value per shareDUOLThe Nasdaq Stock Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company  ☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Item 2.02 Results of Operations and Financial Condition

On February 26, 2026, Duolingo, Inc. (the “Company”) issued a press release announcing the financial results of the Company for the twelve months ended December 31, 2025. A copy of the press release is being furnished as Exhibit 99.1 attached hereto and is incorporated by reference herein.

In accordance with General Instruction B.2 of Form 8-K, the information in this Item 2.02 of this Current Report on Form 8-K, including Exhibit 99.1 attached hereto, shall not be deemed “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Item 8.01 Other Events Duolingo’s Board of Directors has authorized a share repurchase program of up to $400 million. The program reflects the Company’s commitment to capital allocation, including returning capital to stockholders and managing dilution, while maintaining flexibility to invest in long-term growth. Repurchases under the program may be made from time to time in the open market, through privately negotiated transactions or otherwise. The actual timing, number and value of shares repurchased is subject to various factors such as market conditions, the Company’s capital and liquidity positions, contractual requirements and other considerations. The timing and amount of any repurchases will be determined at the Company’s discretion, and the program does not obligate the Company to acquire any particular amount of shares. The program has no expiration date and may be terminated, modified or discontinued at any time. Item 9.01 Financial Statements and Exhibits (d) Exhibits.

Exhibit No.Description

99.1Press Release dated February 26, 2026

99.2Shareholder Letter dated February 26, 2026

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: February 26, 2026 By:/s/ Gillian Munson

Gillian Munson Chief Financial Officer (Principal Financial Officer and Principal Accounting Officer)