一 — Kanji Meaning, Readings & Example Words (JLPT N5)
What it means
At its core, 一 simply means "one." It's the simplest kanji there is — one horizontal line — and it shows up everywhere: counting (一つ, 一人), dates (一月, 一日), and useful set phrases (一番 "the most / number one"). You'll meet it in two roles: as a standalone counting word (一つ "one thing") and as a building block inside compound words (一月 "January," 一番 "number one"). Because it's so common, learning 一 early pays off immediately — you'll be reading prices, dates, and rankings right away.
Readings
| Type | Reading | Used in |
|---|---|---|
| kun'yomi | ひと.つ | 一つ (one thing) |
| kun'yomi | ひと- | 一人 (ひとり, one person — irregular), 一日 (ついたち, the 1st — irregular) |
| on'yomi | イチ | 一 (one), 一番 (number one / most), 一月 (January) |
| on'yomi | イツ | 統一 (とういつ, unification) — less common |
Here's the usual rule of thumb: the kun'yomi (ひと.つ) tends to appear when the kanji stands alone with a hiragana ending, while the on'yomi (イチ) appears inside two-kanji compounds. So 一つ uses ひと.つ, but 一番 and 一月 use イチ. The big exceptions to memorize are 一人 (ひとり) "one person," 一つ (ひとつ), and 一日, which is ついたち when it means "the 1st of the month" but いちにち when it means "one (whole) day." These don't follow the neat pattern, so learn them as fixed words.
Stroke order & radical
- Strokes: 1 — a single horizontal stroke, written left to right. It's the easiest kanji to write, and a good first taste of proper brush direction.
- Radical: 一 is its own radical, the "one" radical (いち). You'll find this single line as a component inside many other kanji, such as 二 (two), 三 (three), and 百 (hundred).
Recognizing that one flat line as a radical is handy: many number and "heaven/sky" kanji are built on top of it.
Common words using 一
Notice the reading split in action: the lone-counter 一つ takes ひと.つ, while compounds like 一月 and 一番 flip to イチ. The two big curveballs are 一人 (ひとり) and 一日 (ついたち) — both irregular, so just memorize them.
Example sentences
ヤッタンはりんごを一つ食べました。
ヤッタンは りんごを ひとつ たべました。
Yattan ate one apple.
一つ — the kun'yomi ひと.つ reading, used for counting things.
モチは一人で図書館へ行きました。
モチは ひとりで としょかんへ いきました。
Mochi went to the library alone.
一人 (ひとり) is an irregular reading meaning 'one person' or 'alone'.
先生は「一番好きな色は何ですか」と聞きました。
せんせいは「いちばん すきな いろは なんですか」と ききました。
Sensei asked, What color do you like the most?
一番 uses the on'yomi イチ; 一番 means 'number one' or 'the most.'
Quick recap
- 一 = one; just 1 stroke; it's the "one" radical itself.
- ひと.つ when counting alone (一つ); イチ in compounds (一月, 一番).
- Memorize the irregulars: 一人 (ひとり), 一日 (ついたち = the 1st / いちにち = one day).
Your turn
Choose the correct reading of 一 in each word.
Start the 5-question drill →Frequently asked questions
How do you read 一 in 一つ vs 一番?
In 一つ it's the kun'yomi ひと (一つ = ひとつ, 'one thing'). In 一番 it's the on'yomi イチ (一番 = いちばん, 'number one / the most'). As a rule, compounds take the on'yomi.
Why is 一人 read ひとり?
一人 (ひとり, 'one person / alone') is an irregular reading that doesn't follow the usual pattern. It's a very common word, so it's best to memorize it as a set word. The same goes for 二人 (ふたり, 'two people').
Is 一日 read ついたち or いちにち?
Both, depending on meaning. 一日 = ついたち means 'the 1st of the month' (a date). 一日 = いちにち means 'one (whole) day' (a duration). Learn each as a fixed word.
How many strokes does 一 have?
一 has just 1 stroke — a single horizontal line written left to right. It is also the 'one' radical and the simplest kanji to write.