what will be the date of last bitcoin mined?

[gogxmagog]

I have read 2140 as well as 2040, even 2114 once.
which is the correct answer? there's a lot of conflicting numbers.

[strikegold]

just for you 

http://en.wikipedia.org/wiki/Bitcoin

[DannyHamilton]

The EXACT date is impossible to predict.  It will depend on how much hashing power comes online and how fast it comes online.

If blocks were to be solved exactly 10 minutes apart, it would be 2140.  It suppose it could be anywhere from ten years earlier than that to ten years later.

[nightminer]

We are already past the half way mark (11mil+ already mined). This means that we can only mine 10 million in the next 128 years.

Am I missing something? That doesn't sound right.

[martynw2000]

As you get closer to the last coin, the difficulty increases exponentially - meaning you'd need virtually infinite computer power to solve it. Add to that, the reward for finding a block reduces by half every x number of years. By the time we get even remotely close to mining the last coins, it won't be worth the power required.

[Jace]

I have read 2140 as well as 2040, even 2114 once.
which is the correct answer? there's a lot of conflicting numbers.

The correct answer is: never.

The year 2140 is only based on the software's current precision, which divides bitcoins up to 1/100,000,000th. This would imply that around year 2140, the block reward would become zero. However, long before 2140, the precision will be increased (to support smaller fractions of bitcoins, or floating point or whatever) so mining can continue forever.

Mining is never "done" and the actual 21 million will never be reached (although it comes arbitrarily close).

We are already past the half way mark (11mil+ already mined). This means that we can only mine 10 million in the next 128 years.

Am I missing something? That doesn't sound right.

The block reward is reduced exponentially.

Every four years, half of the remaining bitcoins (that's 21 million minus the ones already in existence) are being mined.

[Jace]

As you get closer to the last coin, the difficulty increases exponentially - meaning you'd need virtually infinite computer power to solve it.

That's nonsense. Difficulty only depends on the current hashing power of the network, to ensure that one block is being mined roughly every 10 minutes.

Add to that, the reward for finding a block reduces by half every x number of years. By the time we get even remotely close to mining the last coins, it won't be worth the power required.

Not really - first of all that totally depends on the actual value of a bitcoin at that time, and second, as the block reward becomes smaller and smaller, the transaction fees will become a more and more imporant incentive for miners.

[nightminer]

OK, so it is basically an upside down bell curve.

But guys... that is VERY bad. It technically speaking means that in our lifetime we'll only see around 15 mil (very wild guestimate) in our lifetimes. The last 5 million coins wil take FOREVER to mine.

[Jace]

OK, so it is basically an upside down bell curve.

Correct:

(click = large)

But guys... that is VERY bad. It technically speaking means that in our lifetime we'll only see around 15 mil (very wild guestimate) in our lifetimes. The last 5 million coins wil take FOREVER to mine.

Why is that bad? Remember, mining gold also becomes increasingly difficult. And similarly, it will take FOREVER to dig up the last gold out of the earth.

Knowing that we'll only at most ±15 million also means we know it's guaranteed to be scarce, thus valuable. So get your bitcoins now while you still can afford them

[DannyHamilton]

We are already past the half way mark (11mil+ already mined). This means that we can only mine 10 million in the next 128 years.

Am I missing something? That doesn't sound right.

And yet it is right.

As you get closer to the last coin, the difficulty increases exponentially - meaning you'd need virtually infinite computer power to solve it. Add to that, the reward for finding a block reduces by half every x number of years. By the time we get even remotely close to mining the last coins, it won't be worth the power required.

You are correct about the fact that the block subsidy "reduces by half" (approximately every 4 years).  The rest of it you have some learning to do.

The year 2140 is only based on the software's current precision, which divides bitcoins up to 1/100,000,000th. This would imply that around year 2140, the block reward would become zero. However, long before 2140, the precision will be increased (to support smaller fractions of bitcoins, or floating point or whatever) so mining can continue forever.

There is no guarantee that this will happen.  It might, but it very well might not.

Mining is never "done" and the actual 21 million will never be reached (although it comes arbitrarily close).

Mining is never done because it will be supported by transaction fees.  In the current design the exact amount of bitcoins created can be calculated, it will be exactly: 20999999.97690000 BTC

Due to the accidental permanent destruction of a few bitcoins by a bug in some mining software, the total unspent outputs in the blockchain will actually be a bit less than that.

But guys... that is VERY bad. It technically speaking means that in our lifetime we'll only see around 15 mil (very wild guestimate) in our lifetimes. The last 5 million coins wil take FOREVER to mine.

Not forever.  15 million will be mined before the end of 2017 (how old are you? I expect to see 20 million mined within my lifetime, in the next 15 years).  It will about 136 years from now until the last bitcoin is mined based on the current implementation.  Why would that be bad?

[nightminer]

Well, it is good in a way that it creates scarcity. So if you own bitcoins right now, those posts on how bitcoin is undervalued bitcoin is are spot on correct.

Bad because 15 mil isn't a lot. Bitcoin wants to be a global currency, and if people really get into the swing of things (ie, bitcoin ATMS - already been done, bitcoin at every online merchant) then there just isn't enough. If just 1 billion of the 6 billion people on the planet start using bitcion, 15 mil for the next few years is nothing. And how many of those coins are under a "digital mattress", stashed away for a rainy day?

Sure I get it, we will all work with 0.00001 bitcoins to buy hosting and tip each other on reddit with 0.00000001 bitcoin - you counted my zero's didn't you

And that's the problem. It becomes unmanageable and can you imagine the amount of typos people will make. 7 zeros... no wait 6 zeros.  Aaah damn I just paid 10 times more than what I was supposed to.

Dont' stone me but my bets are on Litecoin. 84 mil still isn't enough, but it is at least a bit better.

[DannyHamilton]

Well, it is good in a way that it creates scarcity. So if you own bitcoins right now, those posts on how bitcoin is undervalued bitcoin is are spot on correct.

Bad because 15 mil isn't a lot. Bitcoin wants to be a global currency, and if people really get into the swing of things (ie, bitcoin ATMS - already been done, bitcoin at every online merchant) then there just isn't enough. If just 1 billion of the 6 billion people on the planet start using bitcion, 15 mil for the next few years is nothing. And how many of those coins are under a "digital mattress", stashed away for a rainy day?

The software isn't based on "bitcoins", that's just a nickname that we humans use to make it easier to deal with really large amounts.  At the software level everything is represented in "Satoshis" (0.00000001 BTC) as integers.  Basically, the clients all move the decimal over 8 places to the left and call it a bitcoin before displaying it to you, because that was a lot easier to deal with when purchasing a pizza for 10,000 BTC.  Can you imagine if you had to spend 1,000,000,000,000 units to buy the pizza (did you count the zeros)?

Sure I get it, we will all work with 0.00001 bitcoins to buy hosting and tip each other on reddit with 0.00000001 bitcoin - you counted my zero's didn't you

And that's the problem. It becomes unmanageable and can you imagine the amount of typos people will make. 7 zeros... no wait 6 zeros.  Aaah damn I just paid 10 times more than what I was supposed to.

That's a bit like looking at a "penny" and calling it "0.00001 Grand".

Humans have a habit of creating nicknames for common amounts of currency.  Examples: 100 grand, 3 Benjamins, a sawbuck, 13 pennies.

There are already common suggestions for using metric units for the smaller amounts, as well as creating nicknames for every 1/100 of the previous nick name (example bitCents).

Time will tell what nicknames actually end up adopted, but my guess is that it won't be long before 0.00001 bitcoin to buy hosting is listed as 0.01 mBTC (milliBitcoin) or potentially even 10 uBTC (microBitcoin).  No need to count zeros there.

In the end, there will be nearly 2,100,000,000,000,000 (2.1 quadrillion) units, and we can all call them "Satoshis" or whatever other nickname the world settles on decades from now.

[Jace]

Bad because 15 mil isn't a lot. Bitcoin wants to be a global currency, and if people really get into the swing of things (ie, bitcoin ATMS - already been done, bitcoin at every online merchant) then there just isn't enough. If just 1 billion of the 6 billion people on the planet start using bitcion, 15 mil for the next few years is nothing. And how many of those coins are under a "digital mattress", stashed away for a rainy day?

Sure I get it, we will all work with 0.00001 bitcoins to buy hosting and tip each other on reddit with 0.00000001 bitcoin - you counted my zero's didn't you

And that's the problem. It becomes unmanageable and can you imagine the amount of typos people will make. 7 zeros... no wait 6 zeros.  Aaah damn I just paid 10 times more than what I was supposed to.

Obviously, when amounts like 0.00001 BTC become mainstream, we'll simply use smaller units in everyday practice. Like "milliBits" or "milliCoins" as suggested in this thread.

[nightminer]

Thank you Danny, that does put my mind at ease and is great advice in terms of investment. I've been putting all my resources into Litecoin and your post helped me realize.... exchanging 1 LTC for 0.02 bitcoin is actually a lot. 0.02 bitcoin seems so little, but in microBitoins (which we'll all have to adopt very soon if prices keeps shooting through the roof) 0.02 bitcoin is actually A LOT!

Guess it comes down to that we have to re-adjust our thinking and stop looking at bitcoin in terms of the 2 decimal system.

I enjoyed this conversation, gave me a lot to think about!

@Jace - saw your post after I made the post above. Thank you for the link. It does clear things up!

[Dabs]

The gamblers already use ksats. Kilo Satoshis.

I personally don't mind using bitcoins with 8 decimal places. I've gotten used to it. Besides, you're not going to pay much attention to any value below the minimum transaction fee of (currently) 0.0001.

[nobbynobbynoob]

Most bitcoin will have been mined out by the 2030s. By current reckoning, the last satoshi will be mined circa 2140, assuming that bitcoin still exists then and hasn't been subdivided even more.

[MAbtc]

The actual last bitcoin? We'll be gone by then. 

But most bitcoins will have been mined long, long before that. 

[lindeanin]

you forgot something
every 18 month the pc power get doubled till 2029 (*intel developer/manager)

And? Thats why the difficulty is adjusting every 2016 mined blocks...

[Dabs]

https://en.bitcoin.it/wiki/Controlled_supply

This one looks better.

By the year 2020 there will be 17718750 bitcoins at the start of the year.
By the end of 2024, there will be 20 million bitcoins.

The last million bitcoins will then be mined over the next hundred years.

Or another way of saying it is:
99% of all bitcoins will have been mined by 2032. The last one percent will be mined for a hundred years.

I don't know how many ASICs or peta or exa hashes we will be, but bitcoin can only rise in value compared to how it is used today. So today, bitcoins are relatively cheap, even at $130 USD.

[Dabs]

June 24 2020 is the estimated date to hit the limit

I don't know how you arrived at that date.