Upon his resurrection through the Dragon Balls, Goku remains physically 23 but chronologically ages to 24 when he helps drive Vegeta from the Earth.
After defeating Buu, Dragon Ball Z has a 10-year time jump for its epilogue. Goku's chronological age at the end of Dragon Ball Z is 44, however, his body is that of 37.
While Goku believes he's 14 years old, the next story arc reveals that he actually couldn't count and is much younger than he suggests. Goku is actually around eleven years old during the Son Goku Saga, which includes the Emperor Pilaf and Tournament Sagas.
At the beginning of the saga, Goku told Bulma that he was 14, but that was because Goku's lack of education left him with an inability to count properly. After studying with Master Roshi, Goku became smart enough to at least know that 12, which was his actual age in his introduction, came after 11, and not 14.
Goku was born in April 16 age 736 in planet Vegeta. We're gonna use this age because it's the one in the Manga, in the anime he was born in age 737. Three years later in age 739, right before the destruction of planet Vegeta he is sent to earth.
As such, Goku will not begin to grow old until 1000 years have passed in which the series will likely end. And this is all counting the idea that use of god-ki may make him further immortal. So fear not, fans. Goku will not grow old on us and die.
According to the Daizenshuu, a Dragon Ball encyclopedia, a saiyan's lifespan is about the same as an average Human (70 to 90 years, with exceptions, of course), but keep in their peak longer. Unlike humans, saiyans remain in their youth and prime much longer. Which Goku is actually smarter, GT Goku or Super Goku?
When Goku was killed by Cell, he declined to be wished back by the power of the Dragon Balls. As a result, he remained dead for seven years. He wasn't resurrected until the end of the Buu Saga. Since Goku wasn't technically alive during this period, he didn't age during his time in Otherworld.
After both Goku and the series experienced a 10-year time jump for the epilogue, Goku was now physically 37 and chronologically 44, while Vegeta also points out Saiyans' aging slows once they hit their physical prime to fight longer and more effectively.
Another notable change is death. The biggest example is Goku, who was dead for seven years, causing him not to age, thus making him physically the same age he was when he died upon his return to Earth, and this is clearly noted.
Goku after the 1,000 year time-skip in Dragon Ball Omniverse. He first appeared in the Return of the Gods Saga to help Adrian fight Majin Beegito. His debut was short as he was killed immediately. He has been shown to be an entirely different version of Goku and may be a completely different being.
Goku was born in Age 736 737 and Vegeta was born in Age 732. Vegeta was 4 5 years older than Goku. Since then a couple of things have happened. First, Vegeta has spent more time in the Hyperbolic Time Chamber than Goku.
10 How Old Is Vegeta
Vegeta's official birth year is Age 732, making him 48 years old by the end of Dragon Ball Super in Age 780. However, this doesn't take into account the amount of time he has spent inside the Hyperbolic Time Chamber, which he has spent a collective 5 years inside.
112.5+80= 192.5 years total in an average healthy Saiyan male, astonishing.
Goku is functionally immortal thanks to the wishes granted via the Dragon Balls and his good standing with multiple different tiers of Gods in the Dragon Ball universe (and parallel universes).
In-universe, Goku dies on November 28 and is revived on November 3 of the next year in order to fight Nappa and Vegeta. Goku later sacrifices his life at the end of the Cell Games, opting to stay dead for seven years before having his life restored by the Rou Kaioshin during the events of the Majin Buu arc.
"Saiyans are a warrior race, so their aging slows once they reach an age suitable for fighting, and they maintain great strength for a long time. However, their lifespan is not much different from Earthlings', and when they reach a certain age, they rapidly grow frail," Toriyama said (via Kanzenshuu).
Xicor, Goku's 3rd and Strongest Son.
In the very first chapter of Dragon Ball, the male protagonist introduces himself to the female protagonist as “Goku” with a direct follow-up to that: his full name is “Son Goku”. In typical Japanese fashion, the family name here comes first (“Son”) followed by the given name (“Goku”).
Many fans consider Jiren to be stronger than Goku based on the exceptional abilities and feats that he demonstrated in the Tournament of Power arc. He possesses an overwhelming amount of power and strength.
Multiply that by 100 and Timeskip Base GT Goku would be 6400x stronger than Omega Shenron. With that amount of strength his power would be more comparable to MUI Moro arc Goku while only using SSJ.
Goku, being a Saiyan, has a much slower aging process than humans. However, it is not confirmed whether he has completely stopped aging or not. In the Dragon Ball series, Goku's age is shown to increase gradually, but at a significantly slower pace than that of humans.
In short, Goku's biological age is reduced to 39 years.