Leap-month reference, 1901–2100
Reading the table
This reference lists every lunar year beginning from 1901 through 2100. The year label is the Gregorian year in which that lunar year begins. A month near the end of a lunar year may continue into January of the following Gregorian year.
“Leap 6” means an additional month after ordinary month six and before month seven. “None” means the lunar year has twelve months. The Gregorian start is lunar day one, and “Days” gives the complete month length. To find the last day, add one less than the stated length to the start date.
Leap months, 1901–2100
The full 200-year list contains 73 years with a leap month and 127 without one.
1901–1950
| Lunar year | Leap month | Gregorian start | Days |
|---|---|---|---|
| 1901 | None | — | — |
| 1902 | None | — | — |
| 1903 | Leap 5 | 1903-06-25 | 29 |
| 1904 | None | — | — |
| 1905 | None | — | — |
| 1906 | Leap 4 | 1906-05-23 | 30 |
| 1907 | None | — | — |
| 1908 | None | — | — |
| 1909 | Leap 2 | 1909-03-22 | 29 |
| 1910 | None | — | — |
| 1911 | Leap 6 | 1911-07-26 | 29 |
| 1912 | None | — | — |
| 1913 | None | — | — |
| 1914 | Leap 5 | 1914-06-23 | 30 |
| 1915 | None | — | — |
| 1916 | None | — | — |
| 1917 | Leap 2 | 1917-03-23 | 29 |
| 1918 | None | — | — |
| 1919 | Leap 7 | 1919-08-25 | 30 |
| 1920 | None | — | — |
| 1921 | None | — | — |
| 1922 | Leap 5 | 1922-06-25 | 29 |
| 1923 | None | — | — |
| 1924 | None | — | — |
| 1925 | Leap 4 | 1925-05-22 | 30 |
| 1926 | None | — | — |
| 1927 | None | — | — |
| 1928 | Leap 2 | 1928-03-22 | 29 |
| 1929 | None | — | — |
| 1930 | Leap 6 | 1930-07-26 | 29 |
| 1931 | None | — | — |
| 1932 | None | — | — |
| 1933 | Leap 5 | 1933-06-23 | 30 |
| 1934 | None | — | — |
| 1935 | None | — | — |
| 1936 | Leap 3 | 1936-04-21 | 30 |
| 1937 | None | — | — |
| 1938 | Leap 7 | 1938-08-25 | 30 |
| 1939 | None | — | — |
| 1940 | None | — | — |
| 1941 | Leap 6 | 1941-07-24 | 30 |
| 1942 | None | — | — |
| 1943 | None | — | — |
| 1944 | Leap 4 | 1944-05-22 | 30 |
| 1945 | None | — | — |
| 1946 | None | — | — |
| 1947 | Leap 2 | 1947-03-23 | 29 |
| 1948 | None | — | — |
| 1949 | Leap 7 | 1949-08-24 | 29 |
| 1950 | None | — | — |
1951–2000
| Lunar year | Leap month | Gregorian start | Days |
|---|---|---|---|
| 1951 | None | — | — |
| 1952 | Leap 5 | 1952-06-22 | 30 |
| 1953 | None | — | — |
| 1954 | None | — | — |
| 1955 | Leap 3 | 1955-04-22 | 30 |
| 1956 | None | — | — |
| 1957 | Leap 8 | 1957-09-24 | 29 |
| 1958 | None | — | — |
| 1959 | None | — | — |
| 1960 | Leap 6 | 1960-07-24 | 29 |
| 1961 | None | — | — |
| 1962 | None | — | — |
| 1963 | Leap 4 | 1963-05-23 | 29 |
| 1964 | None | — | — |
| 1965 | None | — | — |
| 1966 | Leap 3 | 1966-04-21 | 29 |
| 1967 | None | — | — |
| 1968 | Leap 7 | 1968-08-24 | 29 |
| 1969 | None | — | — |
| 1970 | None | — | — |
| 1971 | Leap 5 | 1971-06-23 | 29 |
| 1972 | None | — | — |
| 1973 | None | — | — |
| 1974 | Leap 4 | 1974-05-22 | 29 |
| 1975 | None | — | — |
| 1976 | Leap 8 | 1976-09-24 | 29 |
| 1977 | None | — | — |
| 1978 | None | — | — |
| 1979 | Leap 6 | 1979-07-24 | 30 |
| 1980 | None | — | — |
| 1981 | None | — | — |
| 1982 | Leap 4 | 1982-05-23 | 29 |
| 1983 | None | — | — |
| 1984 | Leap 10 | 1984-11-23 | 29 |
| 1985 | None | — | — |
| 1986 | None | — | — |
| 1987 | Leap 6 | 1987-07-26 | 29 |
| 1988 | None | — | — |
| 1989 | None | — | — |
| 1990 | Leap 5 | 1990-06-23 | 29 |
| 1991 | None | — | — |
| 1992 | None | — | — |
| 1993 | Leap 3 | 1993-04-22 | 29 |
| 1994 | None | — | — |
| 1995 | Leap 8 | 1995-09-25 | 29 |
| 1996 | None | — | — |
| 1997 | None | — | — |
| 1998 | Leap 5 | 1998-06-24 | 29 |
| 1999 | None | — | — |
| 2000 | None | — | — |
2001–2050
| Lunar year | Leap month | Gregorian start | Days |
|---|---|---|---|
| 2001 | Leap 4 | 2001-05-23 | 29 |
| 2002 | None | — | — |
| 2003 | None | — | — |
| 2004 | Leap 2 | 2004-03-21 | 29 |
| 2005 | None | — | — |
| 2006 | Leap 7 | 2006-08-24 | 29 |
| 2007 | None | — | — |
| 2008 | None | — | — |
| 2009 | Leap 5 | 2009-06-23 | 29 |
| 2010 | None | — | — |
| 2011 | None | — | — |
| 2012 | Leap 4 | 2012-05-21 | 29 |
| 2013 | None | — | — |
| 2014 | Leap 9 | 2014-10-24 | 29 |
| 2015 | None | — | — |
| 2016 | None | — | — |
| 2017 | Leap 6 | 2017-07-23 | 30 |
| 2018 | None | — | — |
| 2019 | None | — | — |
| 2020 | Leap 4 | 2020-05-23 | 29 |
| 2021 | None | — | — |
| 2022 | None | — | — |
| 2023 | Leap 2 | 2023-03-22 | 29 |
| 2024 | None | — | — |
| 2025 | Leap 6 | 2025-07-25 | 29 |
| 2026 | None | — | — |
| 2027 | None | — | — |
| 2028 | Leap 5 | 2028-06-23 | 29 |
| 2029 | None | — | — |
| 2030 | None | — | — |
| 2031 | Leap 3 | 2031-04-22 | 29 |
| 2032 | None | — | — |
| 2033 | Leap 11 | 2033-12-22 | 29 |
| 2034 | None | — | — |
| 2035 | None | — | — |
| 2036 | Leap 6 | 2036-07-23 | 30 |
| 2037 | None | — | — |
| 2038 | None | — | — |
| 2039 | Leap 5 | 2039-06-22 | 29 |
| 2040 | None | — | — |
| 2041 | None | — | — |
| 2042 | Leap 2 | 2042-03-22 | 29 |
| 2043 | None | — | — |
| 2044 | Leap 7 | 2044-08-23 | 29 |
| 2045 | None | — | — |
| 2046 | None | — | — |
| 2047 | Leap 5 | 2047-06-23 | 30 |
| 2048 | None | — | — |
| 2049 | None | — | — |
| 2050 | Leap 3 | 2050-04-21 | 30 |
2051–2100
| Lunar year | Leap month | Gregorian start | Days |
|---|---|---|---|
| 2051 | None | — | — |
| 2052 | Leap 8 | 2052-09-23 | 29 |
| 2053 | None | — | — |
| 2054 | None | — | — |
| 2055 | Leap 6 | 2055-07-24 | 30 |
| 2056 | None | — | — |
| 2057 | None | — | — |
| 2058 | Leap 4 | 2058-05-22 | 30 |
| 2059 | None | — | — |
| 2060 | None | — | — |
| 2061 | Leap 3 | 2061-04-20 | 29 |
| 2062 | None | — | — |
| 2063 | Leap 7 | 2063-08-24 | 29 |
| 2064 | None | — | — |
| 2065 | None | — | — |
| 2066 | Leap 5 | 2066-06-23 | 29 |
| 2067 | None | — | — |
| 2068 | None | — | — |
| 2069 | Leap 4 | 2069-05-21 | 29 |
| 2070 | None | — | — |
| 2071 | Leap 8 | 2071-09-24 | 29 |
| 2072 | None | — | — |
| 2073 | None | — | — |
| 2074 | Leap 6 | 2074-07-24 | 29 |
| 2075 | None | — | — |
| 2076 | None | — | — |
| 2077 | Leap 4 | 2077-05-22 | 29 |
| 2078 | None | — | — |
| 2079 | None | — | — |
| 2080 | Leap 3 | 2080-04-20 | 29 |
| 2081 | None | — | — |
| 2082 | Leap 7 | 2082-08-24 | 29 |
| 2083 | None | — | — |
| 2084 | None | — | — |
| 2085 | Leap 5 | 2085-06-22 | 30 |
| 2086 | None | — | — |
| 2087 | None | — | — |
| 2088 | Leap 4 | 2088-05-21 | 29 |
| 2089 | None | — | — |
| 2090 | Leap 8 | 2090-09-24 | 29 |
| 2091 | None | — | — |
| 2092 | None | — | — |
| 2093 | Leap 6 | 2093-07-23 | 30 |
| 2094 | None | — | — |
| 2095 | None | — | — |
| 2096 | Leap 4 | 2096-05-22 | 29 |
| 2097 | None | — | — |
| 2098 | None | — | — |
| 2099 | Leap 2 | 2099-03-22 | 29 |
| 2100 | None | — | — |
Leap month eleven in 2033
Leap month eleven begins on December 22, 2033 and ends on January 19, 2034. The surrounding months show why a month without a principal term is not automatically a leap month. Dates in each range are inclusive.
| Lunar month | Gregorian range | Principal terms within the month |
|---|---|---|
| Month 8 of 2033 | 2033-08-25–2033-09-22 | None |
| Month 9 of 2033 | 2033-09-23–2033-10-22 | Autumn Equinox, September 23 |
| Month 10 of 2033 | 2033-10-23–2033-11-21 | Frost’s Descent, October 23 |
| Month 11 of 2033 | 2033-11-22–2033-12-21 | Minor Snow, November 22; Winter Solstice, December 21 |
| Leap month 11 of 2033 | 2033-12-22–2034-01-19 | None |
| Month 12 of 2033 | 2034-01-20–2034-02-18 | Major Cold, January 20; Rain Water, February 18 |
| Month 1 of 2034 | 2034-02-19–2034-03-19 | None |
The lunar month containing Winter Solstice is always month eleven. Intercalation depends on the count from the start of one solstice-containing month up to, but excluding, the next. A twelve-month interval has no leap month. A thirteen-month interval assigns the leap label to its first month without a principal term.
Month eight of 2033 belongs to a twelve-month interval, so it remains ordinary. Leap month eleven and month one of 2034 fall in the following thirteen-month interval. Only the first of those months without a principal term receives the leap label.