Amplitude Inc

This proxy statement is furnished in connection with the solicitation by the Board of Directors (the “Board”) of Amplitude, Inc. (“we,” “us,” “our,” the “Company” or “Amplitude”) of proxies to be voted at our 2025 Annual Meeting of Stockholders to be held on Thursday, June 12, 2025, at 9:00 a.m. PT (the “Annual Meeting”), and at any continuation, postponement, or adjournment of the Annual Meeting. The Annual Meeting will be a completely virtual meeting, which will be conducted via live audio-only webcast. There is no physical location for the Annual Meeting. We believe that hosting a virtual meeting will facilitate stockholder attendance and participation at our Annual Meeting by enabling stockholders to participate from any location around the world. We have designed the virtual meeting to provide the same rights and opportunities to participate as stockholders would have at an in-person meeting, including the right to vote and ask questions during the Annual Meeting through the virtual meeting platform. You will be able to attend and participate in the Annual Meeting online, vote your shares electronically and submit your questions during the Annual Meeting by visitingwww.virtualshareholdermeeting.com/AMPL2025 at the meeting date and time. Please refer to “What will I need in order to attend the Annual Meeting?” below for information on how to register and attend the Annual Meeting. The mailing address of our principal executive offices is Amplitude, Inc., 201 3rd Street, Suite 200, San Francisco, California 94103.

Holders of record of outstanding shares of Class A common stock, $0.00001 par value per share (“Class A common stock”), and Class B common stock, $0.00001 par value per share (“Class B common stock” and, together with the Class A common stock, “common stock”), as of the close of business on April 15, 2025 (the “Record Date”), will be entitled to notice of, and to vote at, the Annual Meeting and any continuation, postponement, or adjournment of the Annual Meeting. The holders of our Class A common stock and Class B common stock will vote as a single class on all matters presented at the Annual Meeting. Each share of Class A common stock is entitled to one vote on each proposal and each share of Class B common stock is entitled to five votes on each proposal. Stockholders are not permitted to cumulate votes with respect to the election of directors. As of the Record Date, there were 98,766,875 shares of Class A common stock outstanding and 32,093,043 shares of Class B common stock outstanding.

IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR THE STOCKHOLDER MEETING TO BE HELD ON JUNE 12, 2025

Pursuant to the rules adopted by the Securities and Exchange Commission (the “SEC”), we have elected to provide access to our Annual Meeting materials, which include this proxy statement and our Annual Report on Form 10-K for the fiscal year ended December 31, 2024 (the “2024 Annual Report”), over the internet in lieu of mailing printed copies. We expect to begin mailing the Notice of Internet Availability to our stockholders of record as of the Record Date for the first time on or about April 25, 2025. The Notice of Internet Availability will contain instructions on how to access and review the Annual Meeting materials and will also contain instructions on how to request a printed copy of the Annual Meeting materials. In addition, we have provided brokers, dealers, banks, voting trustees, and their nominees, at our expense, with additional copies of our proxy materials and the 2024 Annual Report so that our record holders can supply these materials to the beneficial owners of shares of our common stock as of the Record Date.

This proxy statement and our 2024 Annual Report are available at www.proxyvote.com.

PROPOSALS

At the Annual Meeting, our stockholders will be asked:

The Board knows of no other business that will be presented at the Annual Meeting. If any other matter properly comes before the stockholders for a vote at the Annual Meeting, however, the proxy holders named on the Company’s proxy card will vote your shares in accordance with their best judgment.

Recommendations of the Board

The Board recommends that you vote your shares as indicated below. If you return a properly completed proxy card, or vote your shares by phone or internet, your shares of common stock will be voted on your behalf as you direct. If not otherwise specified, the shares of common stock represented by the proxies will be voted, and the Board recommends that you vote:

Information About This Proxy Statement

Why you received this proxy statement. We have made this proxy statement and proxy card available to you on the internet or, upon your request, have delivered printed proxy materials to you, because the Board is soliciting your proxy to vote at the Annual Meeting, including at any continuations, postponements, or adjournments of the Annual Meeting. You are invited to attend the Annual Meeting online to vote on the proposals described in this proxy statement. However, you do not need to attend the Annual Meeting to vote your shares. Instead, you may simply follow the instructions below to submit your proxy over the phone, via the internet, or by mail.

This proxy statement, the Notice of Internet Availability, the notice and accompanying proxy card will be first made available for access on or about April 25, 2025 to all stockholders of record entitled to vote at the Annual Meeting.

Householding. We have adopted a procedure called “householding,” which the SEC has approved. Under this procedure, we deliver a single copy of the Notice of Internet Availability and, if applicable, our proxy materials to multiple stockholders who share the same address unless we have received contrary instructions from one or more of such stockholders. This procedure reduces our printing costs, mailing costs, and fees. Stockholders who participate in householding will continue to be able to access and receive separate proxy cards. We agree to deliver promptly, upon written or oral request, a separate copy of the proxy materials, as requested, to any stockholder at the shared address to which a single copy of those documents was delivered. If you prefer to receive separate copies of the proxy materials, or if you are currently a stockholder sharing an address with another stockholder and wish to receive only one copy of future proxy materials for your household, please write to our Investor Relations department at:

Attention: Investor Relations

201 3rd Street, Suite 200

San Francisco, California 94103

Phone: (650) 988-5131

or atinvestors.amplitude.com/shareholder-services/investor-contacts.

Alternatively, stockholders who received one set of materials due to householding may revoke their consent for future mailings at any time by mail or phone by contacting:

Broadridge Householding Department

51 Mercedes Way

Edgewood, NY 11717

Phone: (866) 540-7095

Street name stockholders may contact their broker, bank, or other nominee to request information about householding.