"time's up" in Japanese

[enyafriend]

I like 時間です . I use it in many situations like:
- my fav show about to begin on the telly
- it's time, we have to go
- time's up/end of a match, competition
- or like MMM says, it's time to put down your pens in an exam
- etc

[html123]

はい、終わり is ok too i think