Quick facts if you are 21
| Born in | 2004 or 2005 |
| Generation | Generation Z |
| Chinese zodiac | Monkey (2004) or Rooster (2005) |
| Days old (approximately) | 7,670 to 8,034 |
How to work it out
Subtract your age from the current year: 2026 − 21 = 2005. That is your birth year if your birthday has already happened this year. If it hasn’t, subtract one more year: 2004. The same rule works for any age, and you can check the result the other way round with our born in 2005 page.
Milestones
Milestones you have already reached:
- 16 (2020 or 2021): Full driver’s license possible in many US states
- 18 (2022 or 2023): Voting age in US elections
- 21 (2025 or 2026): Legal drinking age in the US
Milestones still ahead:
- 25 (2029 or 2030): Car rental usually without a young-driver fee
- 26 (2030 or 2031): Coverage on a parent’s health plan ends (Affordable Care Act)
- 35 (2039 or 2040): Old enough to be President of the United States
- 62 (2066 or 2067): Earliest age to claim (reduced) Social Security benefits
- 65 (2069 or 2070): Medicare eligibility
If you were born in 2005, your Social Security full retirement age is 67; for 2004 it is 67.
Frequently asked questions
If I’m 21, what year will I turn 31?
In 2036 if your birthday has passed this year, otherwise in 2035.
What year did I turn 18 if I’m 21?
In 2023 if your birthday has passed this year, otherwise in 2022.