"What time is it?"
Translation:Wie viel Uhr ist es?
("wie", not "wir".)
I think "Wie spät ist es?" and "Wie viel Uhr ist es?" are both similarly common. Personally, I use both.
It might be that I lean towards "Wie spät...?" when I want to make sure I'm not late / when I want to know how much time I've got left until e.g. the train leaves (because I'm pondering to buy a coffee before it does), and towards "Wie viel Uhr...?" when I'm just curious; but it really doesn't matter which you use.
Yes. "Wie viel Uhr ist es?" and "Wie spät ist es?" are the phrases people use.
"Was ist die Uhrzeit?" sounds like you're asking - in non-standard phrasing, as it can happen in spoken conversation - when something is scheduled, e.g. as an answer to "I've got tickets for that show tomorrow, do you want to come?" or "Mr Boss, you've got a meeting with Mr Important scheduled tomorrow."
...or like you're in the middle of a military-style heist, trying to steal the crown jewels.
Duo suggested "Welche Uhrzeit haben wir?" as a correct answer. why does it have to be "wir" and not "Ich" or anything else?
And also, in the case of "Wie viel Uhr ist es?"- why Uhr and not Uhrzeit? If I wanted to ask "How many clocks are there"? Is the difference only the plural form?
"wir" refers to "humanity", but to that part of it that includes the speaker.
"Welche Uhrzeit haben wir?" isn't common, at least not with the people I know.
But you do say "Welches Datum / Welchen Tag haben wir (heute)?" ("What date / day of the week is it (today)?"), and "Welchen Monat / Welches Jahr...?" as well (although, of course, it's a rare thing to ask). Answer: "Wir haben den sechsundzwanzigsten (Januar)", "Wir haben 2017 / das 21. Jahrhundert" (or formal: "Wir schreiben den 26. Januar / 2018 / das 21. Jahrhundert"), but more commonly (I think) "Heute ist Freitag".
Also: "Welches / Was für ein Wetter haben wir heute / werden wir in Spanien haben?" ("What's the weather today? / What will the weather be in Spain when we are there?"), "Wir haben zehn Grad minus!" ("It's ten degrees below zero!")
Remember that it always refers to the date (or weather) for me, not for other people's as in "What's the time (or weather) in Japan?"
"Wie viel Uhr ist es?" is really just an idiom that doesn't make any grammatical sense (that you could readily see - I'd guess there's some historical explanation).
...which is also why "Wie viel Uhrzeit is es?" doesn't work. "Welche Uhrzeit ist es?" sounds very clumsy (so, basically wrong); a bit better is "Welche Uhrzeit ist es in Japan?" (not recommendable), but the phrases to use are still "Wie viel Uhr / Wie spät ist es in Japan?".
(...and as for the "wir haben" construction: you could colloquially say, "Welche Uhrzeit haben sie (!) (gerade) in Japan?" ("What's the time in Japan (at the moment)?", literally: "What time do they have?"), but that still sounds too clumsy to intentionally say it. I wouldn't recommend it.)
"How many clocks are there?" = "Wie viele Uhren gibt es / sind da/dort?"
I think ‘wie viel Uhr ist es?’ makes sense if you think of (one of the possibilities for) the answer: ‘es ist X Uhr’. It would be like asking ‘how much o'clock is it?’. It's a clever use of ‘wie viel’ for a number that doesn't actually represent a quantity, I find it interesting. A similar usage is ‘der Wievielte ist heute?’ (‘the how-many'th is today?’, to ask for the date), which again substitutes a number with ‘wie viel?’ to ask a question, in a way that would be correct if the number actually represented an amount. I think it makes quite the pun (except it's now a common idiom and I doubt anyone sees the ‘punniness’ of it) and it provides a simple way to ask the question.
We say in german "Wie spät ist es" not "Wie viel Uhr ist es?". You can say both, but often we use "Wie spät ist es?". And when you want to be funny you say "Was sagt die Uhr?" That means "What says the clock?"