Months to Years

How to convert months to years

Divide the months by 12:

years = months ÷ 12

30 months ÷ 12 = 2.5 years. For years and months, keep the whole number of years and the remainder in months: 30 = 2 × 12 + 6, so 2 years 6 months. To go the other way, multiply years by 12.

Converting to weeks or days needs an average, because months are 28 to 31 days long. Over the 400-year cycle of the Gregorian calendar a year averages 365.2425 days, so a month averages 30.44 days, or 4.35 weeks. The converter uses that average; for an exact count between two dates, use the days between dates calculator.

Months to years chart

A child’s age in months

Doctors and parents count a young child’s age in months — 9-month, 18-month and 24-month checkups — and growth charts use months up to age 2 or later. Switching to years at that point is just a division: 30 months is 2½ years. For an exact age from a birth date, use the age calculator.

Loan, lease and contract terms

Car loans, leases, phone contracts and certificates of deposit are usually quoted in months. A 72-month auto loan runs 6 years; a 36-month lease, 3 years; an 18-month promotional rate, a year and a half. Knowing the term in years makes it easier to compare with how long you plan to keep the car or the plan. To find the end date of a term starting today, the date calculator adds months to a date, or see 6 months from today. For weeks, weeks to years; for days, days to months.

Decimal years and rounding

A decimal result is easy to misread. 1.25 years is 1 year and 3 months, not 1 year and 25 months, and 2.75 years is 2 years and 9 months: multiply the decimal part by 12 to get the months back. Some forms round a term to whole years, so a 30-month lease may appear as “2.5 years” on one page and “3 years” on another. When the exact number of months matters — notice periods, warranties, the age limit for a car seat — keep the months and convert only for a rough sense of the length.