Born in
Saint Mary Parish, Jamaica, Williams attended Oracabessa High School before transferring to
Edwin Allen High School in
Clarendon Parish, Jamaica. In 2011, her time of 11.39 seconds for the 100 metres moved her to the top of the world U18 list. She was a bronze medalist in the 100 metres at the
2011 World Youth Championships in
Lille, France, also winning a gold medal in the medley relay at the championships. Williams represented
Jamaica at the
2016 Summer Olympics in
Rio de Janeiro where she was a finalist in the
women's 100 metres event, lowering her personal best to 10.96 seconds. She won a silver medal in the women's 4 x 100 metres at the Games, running in the final alongside
Veronica Campbell-Brown,
Shelly-Ann Fraser-Pryce and
Elaine Thompson as they produced the fifth-fastest time in history of 41.36 seconds, finishing in second place behind the USA, but with the fastest ever time recorded for a second-placed team. Later at the Games, alongside Evans she was a medalist in the
women's 4 x 100 metres relay with
Natasha Morrison and Elaine Thompson.{{Cite web |title= Gold Coast Commonwealth Games|date=15 April 2018 In 2018, Williams ran a personal best in the 60 metres of 7.14 seconds competing on the
2018 IAAF World Indoor Tour in
Glasgow, Scotland. A time she equalled in 2021 at the American Track League in
Arkansas.{{cite web|url= https://trackalerts.com/2021/02/christania-williams-runs-7-14-pb-at-american-track-league/|title=Christania Williams runs 7.14 PB at American Track League|first=Anthony|last=Foster ==Bobsleigh career==