* She is Goku's wife. Goku was born in the year 737 and married Chi-Chi in the year 753. Therefore, she must be around 16 years old at the time of their marriage.
* She is Gohan's mother. Gohan was born in the year 753, shortly after Chi-Chi and Goku married. This means Chi-Chi would have been 16 when Gohan was born.
* She is Goten's mother. Goten was born in the year 767, 14 years after Gohan. This means Chi-Chi was 30 years old when Goten was born.
Taking all of this into account, Chi-Chi is likely in her mid-30s to mid-40s during the events of Dragon Ball Z, and would be even older in Dragon Ball Super.