X0609 4 2026-05-18 0 0001842731 SIMILARWEB LTD. SMWB 0001910424 Offer Or true 87 HAZOREA ST. KFAR SHMARYAHU L3 1 1 0 0 Chief Executive Officer 0 Ordinary Shares 2026-05-18 4 P 0 3105 3.2 A 4641396 D Ordinary Shares 2026-05-19 4 P 0 50000 3.58 A 4691396 D Ordinary Shares 2026-05-19 4 P 0 3000 3.55 A 4694396 D The price reported is a weighted average price. The reporting person undertakes to provide full information, regarding the number of shares and prices at which the transaction was effectuated, upon request. Or Offer by: Oppenheimer Israel, as Attorney-in-fact 2026-05-20