Szilagyi qualified for the women's 100 m butterfly at the 2012 Summer Olympics in London, by completing the event more quickly than the FINA B-standard entry time of 59.07 seconds from the European Championships in Debrecen. She competed with seven other swimmers on the third heat, including three-time Olympians Hannah Wilson of Hong Kong and former Olympic champion Otylia Jędrzejczak of Poland. She achieved sixth place ahead of Portugal's Sara Oliveira by a tenth of a second (0.10) in 1:00.34. Szilagyi failed to advance into the semifinals, as she placed thirty-fourth overall on the first day of preliminary heats.