Grammar › Core Patterns
〜さ — turning an adjective into a noun
Measuring a quality: この山の高さ — the height of this mountain
Dropping the final い of an い-adjective (or attaching directly to a な-adjective stem) and adding さ turns a quality into a measurable noun — 高い (tall) → 高さ (height), 便利 (convenient) → 便利さ (convenience). It's the everyday way to talk about degree or amount of a quality.
How to form it
| Pattern | Example |
|---|---|
| い-adjective: drop い, add さ | 高い → 高さ — height |
| な-adjective + さ | 便利 → 便利さ — convenience |
Example sentences
| Japanese | Reading | Meaning |
|---|---|---|
| この山の高さはどれくらいですか。 | このやまのたかさはどれくらいですか。 konoyamanotakasahadorekuraidesuka。 | About how tall is this mountain? |
| このアプリの便利さに驚いた。 | このあぷりのべんりさにおどろいた。 konoapurinobenrisaniodoroita。 | I was surprised by how convenient this app is. |
| 彼の優しさに助けられた。 | かれのやさしさにたすけられた。 karenoyasashisanitasukerareta。 | I was helped by his kindness. |
🔊 Tap any Japanese sentence to hear it; kanji link to their study pages.
Watch out
さ measures an objective degree or amount (“how tall,” “how convenient”) — for a more subjective, felt impression (“how it feels to be tall”), み is sometimes used instead on a small set of adjectives, though さ is the safe, general-purpose default.