Japanese Months of the Year: Modern and Traditional Names

Japanese months are among the simplest vocabulary sets in the entire language. Unlike French, German, or Spanish (where every month has a unique name you must memorize individually), Japanese uses a perfectly logical formula: number + 月 (gatsu). If you already know the numbers one through twelve, you already know the months.

With approximately 125 million speakers according to Ethnologue's 2024 data, Japanese is the ninth most spoken language in the world. Whether you are planning a trip to see cherry blossoms in April, scheduling a business meeting in Tokyo, or reading a Japanese novel, months appear constantly. The good news is that this particular vocabulary set requires almost zero memorization.

"Japanese is remarkably systematic in its approach to time vocabulary. The numbered month system is one of the most transparent calendrical structures among the world's major languages, making it an ideal early acquisition target for learners."

(David Crystal, The Cambridge Encyclopedia of Language, Cambridge University Press)

This guide covers the modern numbered months, the ancient poetic names still used today, essential grammar patterns, and the cultural events that define each month in Japan.

The 12 Months in Japanese

Every Japanese month follows the same pattern: the Sino-Japanese number (一 through 十二) plus the kanji 月, which means "moon" or "month." The reading of 月 in this context is always gatsu.

That is the entire list. No exceptions, no irregular forms, no gender agreement. The Japan Foundation's 2024 survey notes that months are typically introduced in the first 20 hours of beginner Japanese instruction because of how quickly students can master them.

The Number + 月 System

The beauty of Japanese months lies in their transparency. Once you learn the Sino-Japanese numbers (which you need for counting, dates, prices, and dozens of other contexts) you automatically know the months.

Here is the formula:

Number (一~十二) + 月 (gatsu) = Month name

This system dates to 1873, when the Meiji government adopted the Gregorian calendar and replaced the traditional lunisolar calendar. The decision to use numbered months rather than adapting the old poetic names was deliberate: it aligned Japan with international standards while simplifying official documents and commerce.

The kanji 月 itself is a pictograph of the crescent moon. In the context of month names, it is always read gatsu (がつ). You will encounter the same kanji read as tsuki (つき) when it means "moon" or in certain compound words, and as getsu (げつ) in words like 月曜日 (getsuyōbi, Monday). Context makes the reading clear.

和風月名 (Wafū Getsumai): Traditional Month Names

Before the Meiji era, each month had a poetic name rooted in nature, agriculture, and cultural life. These names are called 和風月名 (wafū getsumai, literally "Japanese-style month names"), and they remain an important part of Japanese literary and cultural identity.

These names paint a vivid picture of life in pre-modern Japan. NINJAL (National Institute for Japanese Language and Linguistics) research traces most of these names to the Nara period (710-794 CE), making them over 1,200 years old.

睦月 (Mutsuki): January

The name means "month of affection" or "month of harmony," reflecting the New Year tradition of families gathering together. The character 睦 means "friendly" or "harmonious."

弥生 (Yayoi): March

One of the most recognizable traditional names, 弥生 means "new life" or "increasing growth," marking the arrival of spring. This name is so embedded in Japanese culture that it became a common female given name and lends its name to the Yayoi period (300 BCE - 300 CE) of Japanese history.

神無月 (Kannadzuki): October

This evocative name means "month without gods." According to Shinto tradition, all the gods of Japan travel to the Izumo Grand Shrine in Shimane Prefecture during October for an annual meeting. The rest of Japan is "without gods" for the month. In Shimane Prefecture alone, October is called 神在月 (kamiarizuki, "month with gods").

師走 (Shiwasu): December

Perhaps the most charming name: "teachers running." The idea is that even Buddhist monks and teachers, normally calm and composed, are so busy with year-end duties that they must run from place to place. Modern Japanese people still use this word to describe the hectic rush of December.

Pronunciation Guide

Japanese month pronunciation is consistent and predictable, but there are a few points that trip up beginners.

The gatsu ending: Always pronounced GAH-tsoo, with the stress on the first syllable. The tsu (つ) sound does not exist in English. It is a voiceless alveolar affricate. Place your tongue behind your upper teeth and release a quick "ts" sound, like the end of "cats."

Four (四) in April: Uses the reading shi (し), not yon. This is the only context where the shi reading is standard for months. The Japan Foundation teaches shigatsu exclusively.

Seven (七) in July: Uses shichi (しち), not nana. Some learners confuse July (shichigatsu) with April (shigatsu); listen for the extra chi syllable in July.

Nine (九) in September: Uses ku (く), not kyū. This shorter reading makes kugatsu crisp and easy to distinguish from other months.

Grammar: Using Months in Sentences

Knowing the month names is only half the battle. You also need to know how to use them in sentences with the correct particles.

Particle に (ni): "in" a month

The particle に marks a specific point in time. Use it when saying something happens in a particular month.

• 四月に学校が始まります。(Shigatsu ni gakkō ga hajimarimasu.) "School starts in April."
• 八月にお盆があります。(Hachigatsu ni Obon ga arimasu.) "Obon is in August."
• 十二月に日本へ行きます。(Jūnigatsu ni Nihon e ikimasu.) "I'm going to Japan in December."

Asking "what month?"

To ask "what month," use 何月 (nangatsu):

• お誕生日は何月ですか？(Otanjōbi wa nangatsu desu ka?) "What month is your birthday?"
• 三月です。(Sangatsu desu.) "It's March."

Counting Duration: ヶ月 (Kagetsu)

One of the most important distinctions in Japanese time vocabulary is the difference between naming a month and counting months as duration.

• 月 (gatsu) = the name of a specific month (三月 = March)
• ヶ月 (kagetsu) = a duration of months (三ヶ月 = three months)

Note the sound changes: one month is ikkagetsu (いっかげつ), not ichikagetsu, and six months is rokkagetsu (ろっかげつ), not rokukagetsu. These are standard phonetic contractions called 促音 (sokuon, double consonants) that make the words flow more naturally.

Cultural Calendar: Key Events by Month

Understanding Japanese months means understanding the cultural rhythm of the year. Japan's calendar is rich with seasonal celebrations, many tied to specific months.

一月 (Ichigatsu): January

正月 (Shōgatsu), New Year, is the most important holiday in Japan. Families gather, visit shrines (hatsumōde), eat traditional foods like おせち料理 (osechi ryōri), and send New Year cards (年賀状, nengajō). Most businesses close from January 1-3.

二月 (Nigatsu): February

節分 (Setsubun) on February 3 marks the transition to spring. People throw roasted soybeans (mamemaki) while shouting 鬼は外、福は内 (Oni wa soto, fuku wa uchi, "Demons out, good fortune in").

三月 (Sangatsu): March

ひな祭り (Hina Matsuri, Girls' Day) on March 3 features elaborate displays of emperor and empress dolls. It is also graduation season for schools across Japan.

四月 (Shigatsu): April

花見 (Hanami), cherry blossom viewing, defines April in Japan. The school year and fiscal year both begin in April, making it a month of new beginnings. NHK dedicates extensive coverage to the sakura zensen (cherry blossom front) as it moves northward across the country.

八月 (Hachigatsu): August

お盆 (Obon) in mid-August is a Buddhist festival honoring ancestors. Many Japanese people return to their hometowns, creating the largest travel rush of the year. Companies typically grant Obon yasumi (Obon vacation) of 3-5 days.

十一月 (Jūichigatsu): November

七五三 (Shichi-Go-San, literally "seven-five-three") on November 15 celebrates children aged 7, 5, and 3. Families dress children in kimono and visit shrines to pray for their healthy growth.

十二月 (Jūnigatsu): December

大晦日 (Ōmisoka) on December 31 is New Year's Eve. Temples ring their bells 108 times (joya no kane) at midnight, representing the 108 earthly desires in Buddhism. Families eat buckwheat noodles (年越しそば, toshikoshi soba) for longevity.

Practice with Real Japanese Content

Months appear constantly in everyday Japanese, from scheduling appointments to discussing seasons to reading event announcements. The seasonal awareness embedded in Japanese culture means that knowing the months connects you to a deeper understanding of how Japanese people experience the year.

Japanese movies and anime are full of month references, especially in slice-of-life stories where seasonal changes drive the narrative. Cherry blossom scenes in April, summer festival episodes in August, and New Year specials in January all reinforce month vocabulary naturally. Check out our guide to the best movies for learning Japanese for films that immerse you in Japan's seasonal rhythm.

Wordy lets you practice month vocabulary in real context by watching Japanese content with interactive subtitles. When a month or date appears in dialogue, you can tap it to see the kanji, hiragana reading, and cultural context. Explore our blog for more Japanese learning guides, or visit our Japanese learning page to start building your vocabulary today.