We cant tell how many actual numbers of bitcoins users are, but just imagine in a world where there is only bitcoin currency and no other currency like Fiat or alt coins. So it means that only then we can say safely that the whole world uses bitcoins

Right, because not everyone doing the interaction in this forum. So there are many out there who are using bitcoin just want to benefit only, so they do not seek out other things in order to be closer to and more about bitcoin bitcoin

There are allot of bitcoin users the value cant be know the only thing you can know is how many coins there are in the world you know
I think there are more than 100 million bitcoin users but i cant knwo for sure offcourse.

100 million??? lol, there isn't even 10 million. I estimate there's at most 2 million people that actively uses Bitcoin tops.

5% seems like a pretty high number to be honest. thats around 370 million people. also less people use bitcoin in third world countries than first world. my estimate is that there are probably around 1-2 million active bitcoin users.

The actual number of bitcoin users cant be known becasue the limit of the bitcoins is not reached yet you know if we reach the bitcoin limit
we will know how many users there are this is not strange why cant you think about this by your self.

I don't think that is possible to find real answer to this question.
In my country I believe that very small number of people using Bitcoin based on activity in this and other forums.
Also, we have only a few merchants which accept bitcoin.
In fact, right now, our concern shouldn't be number of Bitcoin users but how many merchants accept Bitcoin.
If people can use Bitcoin in many different places they will become interesting in Bitcoin and start using it.

If the coinbase shown number of unique users is real, this is a lot of people actually buying Bitcoin. I guess probably most just done only one buy with small amount though, as there is not so high demand to buy Bitcoin at exchanges.

There are probably a lot of people hitting faucets as well for free Bitcoin and probably never bought any Bitcoin at all (otherwise they would not waste to make cents per hour of work). Also interesting places like bitcointalk and r/bitcoin dont have much more users, if really 5 to 10 million of people got any real experience with Bitcoin.

Yes, due to the fact that a single person uses a lot of bitcoin addresses for various reason we can not determine how many people approximately are using bitcoins. Though I am sure they are in hugggge numbers and continuously increasing, no ?

Yes i agree with you and i think we just know amount of volume coins who used by users on this website website https://coinmarketcap.com but there are not guarantee it is true.