Till what time...?

If you want to make a question to the statement "I work until 12", can you say "Till what time do you work?" or do you use "Till when do you work?" instead?

Either, I guess... I would probably say "What time do you work to?" or "What time time do you work until?"

I would usually say, "When do you get off work?"

Both work, and there's a million ways you can ask that question.

I typically say, "When do you work till?"