Rebecca McManus was standing at a Hagley Road West bus stop at 7.50pm when a car ploughed into it and collided with two women.
Rebecca, who was studying creative writing at the University of East Anglia in Norwich, was treated by medical staff but despite their best efforts she died at the scene.
Another woman, also aged 21, was seriously hurt and remains in hospital in a critical condition.
Rebecca’s family have paid tribute to Rebecca as specialist officers continue to liaise with them.
A family statement read: "Rebecca lived life to the full; she was bright and funny with a wonderful future to look forward to.
"We are totally devastated by her loss."
Sergeant Paul Hughes from the force’s Collision Investigation Unit urged witnesses to come forward.
He said: "This is a tragic incident which has left a young member of the local community dead and another critically ill in hospital. I have been overwhelmed by the number of witnesses that have come forward so far but continue to appeal for the public’s help.
He added: "I know the vehicle involved, a red Mitsubishi, travelled along the A4123 Wolverhampton Road before turning onto Hagley Road West, and may have been travelling with another dark-coloured vehicle, possibly a BMW.
"If anyone saw these vehicles then I would ask them to contact me or my team."
He added: "It’s important for the investigation and the families that we piece together all the events and I can only do this with the public’s help."
A 32-year-old man was arrested on suspicion of causing death by dangerous driving and continues to help police with their enquiries.
Anyone with information should contact the collision investigation unit on 101 or alternatively they can leave information anonymously by calling Crimestoppers, the independent charity, on 0800 555 111.