When Goku was born, Master Roshi was 307 years old.

Granpa Gohan was 79 years old when he found Goku in the forest.

Krillin is 1 year older than Goku.

Yamcha and Tien are 4 years older than Goku.

When she met Goku, Bulma was 16 years old .

Goku told Bulma that he was 14 years old when he met her. In the first Tournament, he said he was really 12 years old and that he didn't know how to count before.

At the beginning of the Buu Series Trunks was 6 years old . When Dragonball Z ended Pan was 5 years old .She was 14 at the beginning of Dragonball GT .

Bra was 4 years old when Dragonball Z ended.

The first Tenkaichi Budoukai was held 87 years before Goku was born.

Gohan was 4 when he was first introduced. He trained under Piccolo for one year, then went to Planet Namek for another year. When Future Trunks arrived, Gohan was 7. In the Cell Series, Gohan trained for three years to prepare for the the androids. He was 10 when he trained in the hyperbolic time chamber at Kami's tower. Gohan was 11 when he killed Cell. Gohan entered Orange Star High School when he was 16.

Kami was 900+ years old when he fused with Piccolo.

Dende was 5 years old when he was introduced.