Now, Radcliffe is 27 years old and has two movies lined up to be released in 2017 and 2018.
2. Hermione Granger - Emma Watson.
Watson was 10 years old when she started filming the first movie, and by the last one she was 20.
Today, at the age of 26, she's a prominent figure in the women's rights movement.
3. Ron Weasley - Rupert Grint.
Grint was a little bit older than his co-stars, as he began filming when he was 12 years old (and 13 by the time of the premiere). By the debut of the last film, he was 23.
Now 28 years old, Grint is filming two television series that will debut next year, Snatch and Sick Note.
4. Ginny Weasley - Bonnie Wright.
Ginny was nine when they started filming the first installment, and she turned 20 during the last.
Now 25 years old, Bonnie has continued acting independently.
5. Neville Longbottom - Matthew Lewis.
Lewis was 12 years old when the first movie debuted. Just a few days younger than Daniel Radcliffe, he finished the last movie at the age of 22.
At 27 years, Lewis has not only become extremely handsome, but he has also stayed active both in film and on television.
6. Draco Malfoy - Tom Felton.
Felton was the oldest of the students at 14 years old by the time the first movie had its debut. By the last one, he was 23, almost 24.
Felton just turned 29 years old.
7. Luna Lovegood - Evanna Lynch.
Luna first appeared in Harry Potter and the Order of the Phoenix, when Lynch was 16 years old. By the time the final installment came out, she had already turned 20.
Evanna is now 25 years old, and hasn't appeared in many films or TV shows recently.
8. Fred and George Weasley - James and Oliver Phelps.
The twins were 15 years old when they began pulling their infamous pranks in the Potter universe. By the last movie, they were both 25.
Now 30 years old, the twins haven't appeared in much else.
9. Professor Albus Dumbledore - Richard Harris and Michael Gambon.
Richard Harris played Dumbledore in the first two installments, but he passed away before the third. That's when Michael Gambon took over, playing Dumbledore for the remainder of the series.
Here's Michael Gambon now at 76 years old.
10. Professor Minerva McGonagall - Maggie Smith.
This silent heroine was 67 years old when Harry Potter and the Sorcerer's Stone premiered, and 77 by the premiere of the final installment.
Smith is now 81 years old, and until recently you could see her as Violet Crawley in the series Downton Abbey.
11. Rubeus Hagrid - Robbie Coltrane.
Coltrane was 51 years old the first time he appeared in the series (and no, Hagrid actually isn't that big in real life). Ten years later, he still had that same big heart at 61 years old.
Now 66 years old, Coltrane can be seen in the television movie National Treasure.
12. Professor Severus Snape - Alan Rickman.
Rickman was 55 years old when we first met him in the role of Snape and 65 at the end of the series when we wanted to hug him and cry with him.