〜台(だい)

〜台(だい) counts machines, vehicles, and large appliances.

Counting patterns

Regular pronunciation throughout — this counter has no sound changes:

• 一台(いちだい), 二台(にだい), 三台(さんだい), 四台(よんだい), 五台(ごだい)
• 六台(ろくだい), 七台(ななだい), 八台(はちだい), 九台(きゅうだい), 十台(じゅうだい)
• 何台(なんだい): how many?

What IT counts

• Vehicles: 車(くるま), 自転車(じてんしゃ), バイク, バス
• Electronics: パソコン, テレビ, 冷蔵庫(れいぞうこ), カメラ
• Machines: エアコン, 洗濯機(せんたくき), 掃除機(そうじき), プリンター

The common thread is a self-contained 機械(きかい) — something with a motor, an engine, or a power supply — not the object's shape.

Similar words

• 〜個(こ) counts small objects by shape rather than by function. Small devices sit on the border: a phone or a mouse takes either, with 台(だい) sounding more like equipment and 〜個(こ) more like a small item.
• Long, thin things take 〜本(ほん) even when they are machine parts.
• The independent noun 台(だい) ("stand, platform") is written with the same character but is a separate word, not this counter.