Human time and guinea pig equivalent age:
3 months = 2.5 years old 2 years = 20 years old 5 years = 50 years old 8 years = 80 years old
6 months = 5 years old 3 years = 30 years old 6 years = 60 years old 9 years = 90 years old
1 year = 10 years old 4 years = 40 years old 7 years = 80 years old 10 years = 100 years old

 

A six-monthly health check for your pet guinea pig is equivalent to you visiting the doctor once every five years.