Japanese has a beautiful phrase: 「時の流れ」(とき の ながれ) — "the flow of time." Time is invisible and intangible, yet Japanese kanji slice it into neat, precise units: 年 (year), 月 (month), 日 (day), 時 (hour), 分 (minute), 秒 (second) — layer by layer, down to the very instant.
What makes it even more fascinating is how Japanese divides each day into four stages — 朝・昼・夕・夜 (morning, noon, evening, night) — and names each weekday after a celestial body. These conventions reveal a shared East Asian sense of time that goes back centuries.
In this article, we'll explore 20 fundamental time kanji, covering calendar units, parts of the day, and everything in between.
Core Kanji Table
Calendar Units
| Kanji | On'yomi | Kun'yomi | Meaning | Common Words | Note |
|---|---|---|---|---|---|
| 年 | ネン (nen) | とし (toshi) | year | 今年 (ことし, this year), 来年 (らいねん, next year), 年齢 (ねんれい, age) | Uses on'yomi for dates (2024年 = にせんにじゅうよねん) |
| 月 | ゲツ (getsu)・ガツ (gatsu) | つき (tsuki) | month, moon | 一月 (いちがつ, January), 毎月 (まいつき, every month), 月曜日 (げつようび, Monday) | ガツ for months (January = いちがつ), つき for "every month" |
| 日 | ニチ (nichi)・ジツ (jitsu) | ひ (hi)・か (ka) | day, sun | 今日 (きょう, today), 毎日 (まいにち, every day), 日曜日 (にちようび, Sunday) | One of the most reading-rich kanji: ひ, か, にち, じつ — must be memorized per word |
| 時 | ジ (ji) | とき (toki) | time, hour | 時間 (じかん, time), 時計 (とけい, clock), 時々 (ときどき, sometimes) | 時計 reads とけい (irregular) — memorize it as a set |
| 分 | ブン (bun)・フン (fun)・プン (pun) | わ (wa) | minute, portion | 五分 (ごふん, 5 min), 十分 (じゅっぷん, 10 min), 自分 (じぶん, oneself) | Sound changes with counters: いっぷん, にふん, さんぷん... |
| 秒 | ビョウ (byō) | — | second | 秒速 (びょうそく, speed per second), 一秒 (いちびょう, one second), 秒針 (びょうしん, second hand) | Almost exclusively on'yomi — relatively straightforward |
Parts of the Day
| Kanji | On'yomi | Kun'yomi | Meaning | Common Words | Note |
|---|---|---|---|---|---|
| 朝 | チョウ (chō) | あさ (asa) | morning | 朝食 (ちょうしょく, breakfast), 今朝 (けさ, this morning), 朝日 (あさひ, morning sun) | 今朝 reads けさ — a special compound reading (jukujikun) |
| 昼 | チュウ (chū) | ひる (hiru) | daytime, noon | 昼食 (ちゅうしょく, lunch), 昼間 (ひるま, daytime), 昼寝 (ひるね, nap) | 昼寝 (afternoon nap) is a very common everyday word |
| 夕 | セキ (seki) | ゆう (yū) | evening | 夕方 (ゆうがた, evening), 夕食 (ゆうしょく, dinner), 夕日 (ゆうひ, sunset) | Only two strokes — one of the simplest time kanji |
| 夜 | ヤ (ya) | よる (yoru)・よ (yo) | night | 今夜 (こんや, tonight), 夜中 (よなか, midnight), 夜景 (やけい, night view) | 今夜 = こんや (tonight), 夜中 = よなか (the middle of the night) |
| 午 | ゴ (go) | — | noon | 午前 (ごぜん, AM/morning), 午後 (ごご, PM/afternoon), 正午 (しょうご, noon) | Almost only appears in 午前 and 午後 — rarely used alone |
Past & Present
| Kanji | On'yomi | Kun'yomi | Meaning | Common Words | Note |
|---|---|---|---|---|---|
| 今 | コン (kon)・キン (kin) | いま (ima) | now | 今日 (きょう, today), 今年 (ことし, this year), 今週 (こんしゅう, this week) | Reading changes per compound: 今日 = きょう, 今朝 = けさ |
| 昔 | セキ (seki)・シャク (shaku) | むかし (mukashi) | long ago | 昔話 (むかしばなし, folktale), 昔々 (むかしむかし, once upon a time) | 昔々 = "Once upon a time..." — the classic opening of Japanese fairy tales |
| 曜 | ヨウ (yō) | — | weekday | 曜日 (ようび, day of the week), 月曜 (げつよう, Monday), 火曜 (かよう, Tuesday) | Used exclusively for days of the week — almost never standalone |
| 暦 | レキ (reki) | こよみ (koyomi) | calendar | 西暦 (せいれき, Western calendar), 旧暦 (きゅうれき, lunar calendar) | Japan uses both the Western calendar and the Japanese era system (Reiwa, Heisei...) |
Time Spans
| Kanji | On'yomi | Kun'yomi | Meaning | Common Words | Note |
|---|---|---|---|---|---|
| 旬 | ジュン (jun) | — | 10-day period, in season | 上旬 (じょうじゅん, first 10 days), 旬の食材 (しゅんのしょくざい, seasonal ingredients) | A month splits into 上旬・中旬・下旬; also means "in season" |
| 刻 | コク (koku) | きざ (kiza) | moment, to carve | 時刻 (じこく, time/hour), 刻む (きざむ, to carve), 一刻 (いっこく, a moment) | Historically, one 刻 ≈ 30 minutes; 「一刻も早く」= "as soon as possible" |
| 瞬 | シュン (shun) | またた (matata) | blink, instant | 瞬間 (しゅんかん, instant), 一瞬 (いっしゅん, a split second), 瞬く (またたく, to blink) | 一瞬 (a split second) is extremely common in daily conversation |
| 暫 | ザン (zan) | しばら (shibara) | temporary | 暫く (しばらく, for a while), 暫定 (ざんてい, provisional) | 「しばらくお待ちください」= "Please wait a moment" — essential polite phrase |
| 恒 | コウ (kō) | つね (tsune) | constant, permanent | 恒例 (こうれい, annual custom), 恒常 (こうじょう, permanent), 恒久 (こうきゅう, everlasting) | Mostly used in formal or written language, meaning "unchanging" |
Days of the Week: The Seven Luminaries
Japanese weekdays are called 曜日 (ようび), and each is named after a celestial body — a system rooted in the ancient Chinese concept of the "Seven Luminaries" (七曜):
| Day | Reading | Celestial Body | English |
|---|---|---|---|
| 日曜日 | にちようび | Sun | Sunday |
| 月曜日 | げつようび | Moon | Monday |
| 火曜日 | かようび | Mars | Tuesday |
| 水曜日 | すいようび | Mercury | Wednesday |
| 木曜日 | もくようび | Jupiter | Thursday |
| 金曜日 | きんようび | Venus | Friday |
| 土曜日 | どようび | Saturn | Saturday |
Notice that English weekday names also have celestial origins (Sunday = Sun, Monday = Moon, Saturday = Saturn), but the middle days switched to Norse gods (Tuesday = Tyr, Wednesday = Odin, Thursday = Thor, Friday = Freya). Japanese kept the full planetary naming intact, making it more internally consistent than English.
The Four Stages of a Day: 朝・昼・夕・夜
Japanese divides each day into four distinct time blocks, each with a clear range:
| Stage | Kanji | Reading | Approximate Hours | Greeting |
|---|---|---|---|---|
| Morning | 朝 | あさ | ~6:00–10:00 | おはようございます |
| Daytime | 昼 | ひる | ~10:00–17:00 | こんにちは |
| Evening | 夕 | ゆう | ~17:00–19:00 | (transition zone — either works) |
| Night | 夜 | よる | ~19:00–next morning | こんばんは |
Quick tip: Japan's three main greetings — おはよう, こんにちは, and こんばんは — switch right at the boundaries of these four stages. 夕方 (evening) is the gray zone where either こんにちは or こんばんは is acceptable.
Practice
Q1. What does the 午 in 午前 and 午後 refer to?
Show answer
Noon (12:00). 午 = noon. 午前 = before noon = AM, 午後 = after noon = PM.
Q2. Which celestial body does Wednesday (水曜日) correspond to?
Show answer
Mercury (水星). The seven-day sequence is: 日 (Sun), 月 (Moon), 火 (Mars), 水 (Mercury), 木 (Jupiter), 金 (Venus), 土 (Saturn).
Q3. What days of the month do 上旬, 中旬, and 下旬 refer to?
Show answer
上旬 = 1st–10th, 中旬 = 11th–20th, 下旬 = 21st–end of month. The original meaning of 旬 is "a ten-day period," so each month splits neatly into three 旬.
Q4. What does 「しばらくお待ちください」 mean, and which kanji does it use?
Show answer
"Please wait a moment." It uses the kanji 暫. 暫く (しばらく) = for a while, temporarily. This is one of the most common polite phrases in Japanese service settings.
Q5. How do you read 今朝, and why isn't it "こんちょう" or "いまあさ"?
Show answer
It reads けさ. This is a jukujikun (熟字訓) — a special compound reading where the whole word has a fixed pronunciation that doesn't follow the individual kanji readings. Similar examples: 今日 = きょう, 昨日 = きのう.
Summary
- 年・月・日・時・分・秒 are the six basic units of Japanese timekeeping, progressing from largest to smallest
- 朝・昼・夕・夜 divide each day into four stages, aligned with Japan's three main greetings
- The 曜日 system comes from the ancient Seven Luminaries (seven celestial bodies) — Japanese preserves the full planetary naming
- 旬・刻・瞬・暫・恒 describe time spans of varying length, from ten days to eternity
- Next up: Seasons & Ages — kanji for the cycle of seasons and the stages of life