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Ever wondered why no one can agree on the exact time the BTC halving is going to happen?
As of this writing, we’re still yet to see the exact same countdown on any two sources (see header pic 
).
So what’s going on?
Turns out, there are three elements to this: the block at which the next halving occurs, the current block height, and the average block time.
Since the block at which the next halving occurs is a constant, that can’t be it…
While the block height may vary, it’s always known so the calculations should be consistent; so that ain’t it either…
The uniquely disputed one is the average block time (which sounds kind of boring, but gets more interesting as you dig deeper into it).
By design, theoretically the time to mine a block should be an even 10 minutes.
But the amount of miners directing computational power to mine and secure the Bitcoin blockchain changes constantly, meaning that sometimes that can be more than 10 mins, sometimes less.
What most halving calculators seem to be doing is taking the rolling average block time over some arbitrary period of time (e.g. the past 100, 90 or 30 days).
As a result, we get estimates that range all over the place – and the truth is no one will really know when the halving will occur, until the very last block to be mined.
Alright, now you know. Happy Monday!
