Exhibit 99.1 SIMILARWEB ANNOUNCES FIRST QUARTER 2023 RESULTS First quarter 2023 revenue grew 19% year-over-year to 52.8million•Cashandcashequivalentstotaled75.3 million as of March 31, 2023, compared to 77.8millionasofDecember31,2022.•Netcashprovidedbyoperatingactivitieswas0.3 million, compared to 0.9millionforthefirstquarterof2022.•Freecashflowwas(1.2) million, compared to (4.3)millionforthefirstquarterof2022.•Normalizedfreecashflowwas(0.6) million, ...