X0508 4 2025-11-07 false 0001866692 Amplitude, Inc. AMPL 0002032390 Casey Andrew C/O AMPLITUDE, INC. 201 3RD STREET, SUITE 200 SAN FRANCISCO CA 94103 false true false false Chief Financial Officer false Class A Common Stock 2025-11-07 4 P false 30000.00 9.993 A 1160608.00 D This transaction was executed in multiple trades at prices ranging from $9.90 to $10.07, inclusive. The price reported in Column 4 above reflects the weighted average price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares purchased at each respective price within the range set forth in this footnote. Includes 883,657 RSUs. Includes 2,500 shares acquired under the Issuer's employee stock purchase plan on May 14, 2025. /s/ Elizabeth Fisher, as attorney in fact for Andrew Casey 2025-11-12