Months in Korean: 일월 to 십이월, with hanja, IPA and date order

Number plus 월: how the Korean months are built

Korean gave up month names in the European sense. Every month is counted, using the Sino-Korean numerals 일, 이, 삼, 사 and so on, and the syllable 월 (月), which also stands alone for month in the sense of a calendar unit. Learning the months in Korean therefore costs nothing beyond counting from one to twelve, and the Korean numbers page has those.

The native counting words never appear in month names. A Korean speaker counts apples with 하나, 둘, 셋, but January is never 하나월. The split follows a general pattern in the language: dates, money and minutes take the Sino-Korean series, according to Wikipedia's article on Korean numerals.

In print the months are almost always written with Arabic digits, 1월 to 12월. The Unicode CLDR locale data, which phones and computers use to format Korean dates, has only these digit forms, for the full and the short month name alike. Read aloud, 6월 is still 유월 and 10월 is still 시월.

Why June is 유월 and October is 시월

Six is 육 and ten is 십, so the regular forms would be 육월 and 십월. Nobody says them. The Hangul Orthography published by the National Institute of Korean Language covers the case in article 52: where a Sino-Korean word is pronounced both with the original reading of a character and with a customary one, each word is written as it is pronounced. Its example list sets 오륙십, fifty or sixty, against 오뉴월 and 유월, and 십일, the tenth day, against 시월.

In both words the customary form simply lacks the final consonant of the numeral: the k of 육 and the p of 십 are gone. The orthography records the spoken result, and the hanja 六月 and 十月 keep the etymology visible.

The change is limited to these words. November and December keep their 십: 십일월 and 십이월, sibirwol and sibiwol. And the digits hide the whole matter on paper, since 6월 and 10월 are written exactly like the other ten months.

The related word 오뉴월, May and June together, shows the same customary reading.

Writing a date: year, month, day

Korean dates run from the largest unit to the smallest. The year takes 년, the month 월 and the day 일, so 28 October 2026 is 2026년 10월 28일. The long date pattern in CLDR is exactly that, y년 MMMM d일, and the full pattern adds the weekday at the end: 2026년 10월 28일 수요일.

Short dates replace the words with full stops and spaces: the medium CLDR pattern gives 2026. 10. 28., with a stop after the day as well.

Asking for the date uses 며칠, what day of the month: 오늘이 며칠이에요? The spelling 몇일 is a common mistake. Wiktionary traces 며칠 to Middle Korean 며츨 and explains the misspelling as a folk analysis into 몇, how many, plus Sino-Korean 일, day.

Months in Korean also combine with 달, the native word for moon and month. With the contracted numerals it counts durations, 한 달 for one month, and three months can be 석 달, a form given in Wikipedia's article on Korean numerals.

The lunar calendar and its older month names

Alongside the Gregorian months, Korea keeps a lunisolar calendar for its traditional festivals. Its months are numbered in the same way, but some carry older names. According to Wikipedia's article on the Korean calendar, the first month is 정월, the primary month, the eleventh 동짓달, the month of the winter solstice, and the twelfth 섣달, the closing month of the year.

The same article lists a set of zodiac names in which an animal joins 달: 호랑이달, the tiger month, for the first, 토끼달, the rabbit month, for the second, and 돼지달, the pig month, for the tenth.

The lunar dates matter because the two biggest holidays follow them. Seollal, the lunar new year, falls on the first day of the first lunar month, and Chuseok, the harvest festival, on the fifteenth day of the eighth. Their Gregorian dates therefore move from year to year.