How it works
Years = months ÷ 12. Months = years × 12. Approximate days = months × (365.2425 ÷ 12). Approximate weeks = approximate days ÷ 7.
- Choose months to years or years to months.
- Enter an amount, including decimals if needed.
- Read the years and months; treat days and weeks as approximate.
Worked example: 18 months ÷ 12 = 1.5 years, or 1 year 6 months. On the Gregorian average, this is about 547.86 days or 78.27 weeks. A 360-month mortgage term is 30 years.
Common month durations
| Months | Years | Years and months | Approx. weeks | Approx. days |
|---|---|---|---|---|
| 6 | 0.5 years | 0 years 6 months | 26.09 weeks | 182.62 days |
| 9 | 0.75 years | 0 years 9 months | 39.13 weeks | 273.93 days |
| 12 | 1 year | 1 year 0 months | 52.18 weeks | 365.24 days |
| 18 | 1.5 years | 1 year 6 months | 78.27 weeks | 547.86 days |
| 24 | 2 years | 2 years 0 months | 104.36 weeks | 730.49 days |
| 30 | 2.5 years | 2 years 6 months | 130.44 weeks | 913.11 days |
| 36 | 3 years | 3 years 0 months | 156.53 weeks | 1,095.73 days |
| 48 | 4 years | 4 years 0 months | 208.71 weeks | 1,460.97 days |
| 60 | 5 years | 5 years 0 months | 260.89 weeks | 1,826.21 days |
| 120 | 10 years | 10 years 0 months | 521.78 weeks | 3,652.43 days |
| 240 | 20 years | 20 years 0 months | 1,043.55 weeks | 7,304.85 days |
| 360 | 30 years | 30 years 0 months | 1,565.33 weeks | 10,957.28 days |
Swipe the table sideways to see the rest.
Years and months use exactly 12 months per year. Days and weeks are approximate averages.
Things to consider
- Children's ages are often given in months up to 24 or 36.
- Use the Age Calculator for age from a birth date.
- 60 months is 5 years; 360 months is 30 years.
- Use the Mortgage Calculator to compare repayment terms.
- Check start and end dates for leases and contracts.
- Work experience in months converts with the same 12-month rule.
Frequently asked questions
How many months are in a year?
There are exactly 12 calendar months in a year. Two years contain 24 months and five years contain 60 months. Leap years still have 12 months.
How do I convert months to years?
Divide the number of months by 12. For example, 30 ÷ 12 = 2.5 years. To go the other way, multiply years by 12: 2.25 years is 27 months.
What is 18 months in years?
18 months is 1.5 years, or 1 year 6 months. Children's ages are often stated in months up to 24 or 36 months. The Age Calculator can calculate age from an actual birth date.
Why do days per month vary?
Calendar months have 28, 29, 30 or 31 days. This converter uses the Gregorian average month, 365.2425 ÷ 12 = 30.436875 days, for approximate days and weeks. The Days to Years Converter and Weeks to Years Converter use the same year convention.
How do I convert an exact span between dates?
Use the Days Calculator: Days Between Two Dates for an actual day count. Use the Date Calculator: Add or Subtract Days to move a date by a day offset. Average month lengths cannot give an exact calendar span.
Can I convert loan terms, leases or work experience?
Yes. A 60-month term is 5 years and 360 months is 30 years. The Mortgage Calculator can use the term for repayment estimates. For leases, contracts and work experience, check the actual start and end dates rather than treating average days as a legal date calculation.
Results are estimates for general information only, not financial, medical or professional advice.