Translation guide
A zip fastener (zipper) is a common clothing fastener. In Japanese, it is most often called ファスナー or ジッパー. The verb 'to zip' uses 閉める (しめる) or 上げる (あげる), and 'to unzip' uses 開ける (あける) or 下げる (さげる).
Referring to the zipper as an object on clothing, bags, etc.
The most common and neutral word for 'zipper' in Japanese. Used in everyday conversation and writing.
このジャケットのファスナーが壊れた。
The zipper on this jacket broke.
Also common, slightly more casual or brand-oriented. Often used for bags and outdoor gear.
ジッパーを閉めてください。
Please close the zipper.
A dated or colloquial term, originally from 'chuck' (a brand name). Still understood but less common today. May sound old-fashioned.
チャックが開いてるよ。
Your fly is open.
Expressing the action of closing a zipper.
The standard way to say 'to zip up'. 閉める means 'to close'. Works for any zipper.
寒いので、ジャケットのファスナーを閉めた。
It was cold, so I zipped up my jacket.
Literally 'to raise the zipper'. Very natural for vertical zippers (jackets, dresses). Implies pulling the slider upward.
ファスナーを一番上まで上げて。
Zip it all the way up.
Same as ファスナーを閉める, using ジッパー instead. Slightly more casual.
バッグのジッパーをちゃんと閉めて。
Close the bag's zipper properly.
Expressing the action of opening a zipper.
The standard way to say 'to unzip'. 開ける means 'to open'.
ファスナーを開けて、中を見せて。
Unzip it and show me what's inside.
Literally 'to lower the zipper'. Natural for vertical zippers when pulling the slider down.
ファスナーを少し下げて。
Unzip it a little.
Same as ファスナーを開ける, using ジッパー.
ジッパーが固くて開けられない。
The zipper is stuck and I can't open it.
Describing a zipper that doesn't work properly.
Means the zipper is caught or stuck. Very common expression.
ファスナーが引っかかって動かない。
The zipper is stuck and won't move.
Means the zipper is broken (e.g., teeth missing, slider off).
ファスナーが壊れたから、新しいのを買わないと。
The zipper broke, so I have to buy a new one.
ファスナー is the safest, most widely understood word. ジッパー is also fine, especially for bags and casual contexts. チャック is old-fashioned and best avoided unless you're going for a retro feel or warning someone their fly is down.
閉める/開ける are general 'close/open' verbs and work for any zipper. 上げる/下げる (raise/lower) are more vivid for vertical zippers but can sound odd for horizontal ones (like on a bag). When in doubt, use 閉める/開ける.