The 12 Months of the Year
The 12 months of the year, in order, are January, February, March, April, May, June, July, August, September, October, November and December. Seven months have 31 days, four have 30, and February has 28 (29 in leap years).
Updated · By the YearlyCalendar.org team
The 12 months in order
Month names link to the 2026 calendar for that month. AP style abbreviates a month only before a specific date (Sept. 7) and never shortens March to July. Seasons are meteorological (whole months); astronomical seasons start at the equinoxes and solstices: first day of spring, first day of summer, first day of fall, first day of winter.
| No. | Month | Abbr. | AP style | Days | Quarter | Season (north) | Season (south) |
|---|---|---|---|---|---|---|---|
| 1 | January | Jan | Jan. | 31 | Q1 | Winter | Summer |
| 2 | February | Feb | Feb. | 28 (29 in leap years) | Q1 | Winter | Summer |
| 3 | March | Mar | March | 31 | Q1 | Spring | Fall |
| 4 | April | Apr | April | 30 | Q2 | Spring | Fall |
| 5 | May | May | May | 31 | Q2 | Spring | Fall |
| 6 | June | Jun | June | 30 | Q2 | Summer | Winter |
| 7 | July | Jul | July | 31 | Q3 | Summer | Winter |
| 8 | August | Aug | Aug. | 31 | Q3 | Summer | Winter |
| 9 | September | Sep | Sept. | 30 | Q3 | Fall | Spring |
| 10 | October | Oct | Oct. | 31 | Q4 | Fall | Spring |
| 11 | November | Nov | Nov. | 30 | Q4 | Fall | Spring |
| 12 | December | Dec | Dec. | 31 | Q4 | Winter | Summer |
Where the month names come from
| Month | Latin name | Origin of the name | Birthstone |
|---|---|---|---|
| January | Ianuarius | Named after Janus, the Roman god of doorways and beginnings. | Garnet |
| February | Februarius | From Februa, a Roman festival of purification held mid-month. | Amethyst |
| March | Martius | Named after Mars, the Roman god of war; it was the first month of the early Roman year. | Aquamarine |
| April | Aprilis | Probably from the Latin aperire, "to open", for the opening buds of spring. | Diamond |
| May | Maius | Named after Maia, a Greek and Roman goddess of growth. | Emerald |
| June | Iunius | Named after Juno, the Roman queen of the gods and patron of marriage. | Pearl / Alexandrite |
| July | Iulius | Named in honor of Julius Caesar, who was born in this month. | Ruby |
| August | Augustus | Named in honor of Augustus, the first Roman emperor. | Peridot |
| September | September | From the Latin septem, "seven" — it was the seventh month of the old Roman calendar. | Sapphire |
| October | October | From the Latin octo, "eight" — the eighth month of the old Roman calendar. | Opal / Tourmaline |
| November | November | From the Latin novem, "nine" — the ninth month of the old Roman calendar. | Topaz / Citrine |
| December | December | From the Latin decem, "ten" — the tenth month of the old Roman calendar. | Turquoise / Tanzanite |
A short history of the 12 months
The early Roman calendar. According to Roman tradition, the first calendar had 10 months, from March (Martius) to December, which is why September to December are named after the Latin numbers seven to ten. January and February were added later, traditionally by King Numa Pompilius. From 153 BC the Roman year began on January 1, when new consuls took office.
The Julian calendar. Julius Caesar introduced a solar calendar of 365 days with a leap day every four years in 46 BC; it took effect in 45 BC. The month Quintilis was renamed Iulius (July) in his honor in 44 BC, and Sextilis became Augustus (August) in 8 BC.
The Gregorian calendar. Pope Gregory XIII corrected the drift of the Julian calendar in 1582: Thursday, October 4 was followed by Friday, October 15. Britain and its colonies, including those in America, switched in 1752, when Wednesday, September 2 was followed by Thursday, September 14. The month names and lengths stayed the same. How the leap year rule works.
How to remember the days in each month
The rhyme: Thirty days hath September, April, June and November. All the rest have thirty-one, excepting February alone, which hath but twenty-eight days clear, and twenty-nine in each leap year.
The knuckle method: make a fist and count the months across your knuckles and the dips between them, starting with January on the first knuckle. Months on a knuckle have 31 days; months in a dip have 30 (or 28–29 for February). After July on the last knuckle, start again on the first knuckle with August — which is why July and August both have 31 days.
Seven months have 31 days (January, March, May, July, August, October, December), four have 30 (April, June, September, November), and February has 28 or 29.
Frequently asked questions
How many weeks are in a month?
Four full weeks plus 0 to 3 days: February has exactly 4 weeks (4 weeks and 1 day in a leap year), 30-day months have 4 weeks and 2 days, and 31-day months 4 weeks and 3 days. On average a month is about 4.35 weeks.
Which months start on the same day of the week?
In a common year: January and October; February, March and November; April and July; September and December. In a leap year: January, April and July; February and August; March and November; September and December. Months in the same group have identical calendar layouts.
Which month has the most US federal holidays?
January and November, with 2 each in 2026: January (New Year's Day, Martin Luther King Jr. Day); November (Veterans Day, Thanksgiving Day).