Looking on the internet deeply has found these results:

what time is the most popular phrase on the web.

which time 11,530,000 results on the web	what time 156,900,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Do not, however, try to say "which time is it", when asking for the time at the moment. In a situation where choice is important, you could say which: [I'm starting�... Dec 31, 2013 ... I am confused with the grammar here. Which is grammatically correct? At which time will you call me? At what time will you call me? And why? Aug 14, 2013 ... Example with a specific choice: This show is on in the morning and in the evening. At which time of (the) day do you usually watch it? dubitans�... This also cannot be a relative clause, but I imagine it can also be used like 'after which time' in that it can be separated by a main clause by a�...	I didn't know what time you were leaving... I'm just seeing what time it is. Find out what time the track opens. I wasn't sure what time you'd be arriving. 22 minutes door to door, And that girl just asked me what time it was. I can't remember what time the appointment was.

which time

11,530,000 results on the web

what time

156,900,000 results on the web

More popular!

Do not, however, try to say "which time is it", when asking for the time at the moment. In a situation where choice is important, you could say which: [I'm starting�...
Dec 31, 2013 ... I am confused with the grammar here. Which is grammatically correct? At which time will you call me? At what time will you call me? And why?
Aug 14, 2013 ... Example with a specific choice: This show is on in the morning and in the evening. At which time of (the) day do you usually watch it? dubitans�...
This also cannot be a relative clause, but I imagine it can also be used like 'after which time' in that it can be separated by a main clause by a�...