Born in Aiud, Alba County, Rațiu moved to Aragon, Spain at the age of six[1] and joined Villarreal's youth setup from Andorra CF.
[2] He made his senior debut with the C-team on 20 August 2016, coming on as a second-half substitute in a 2–2 Tercera División away draw against Alzira.
[4] After being regularly used with the C-side, Rațiu made his debut for the reserves on 17 December 2017, replacing Darío Poveda late into a 3–2 home win against Peña Deportiva in the Segunda División B championship.
[13] On 2 September 2021, Rațiu debuted for the Romanian national team in a 2–0 victory over Iceland in the 2022 World Cup qualifiers, starting the match and coming off after 68 minutes.
[14] On 26 September 2022, he scored his first goal in a 4–1 defeat of Bosnia and Herzegovina, which had already won its UEFA Nations League group at that point.