102

People say the total will be 21000000 BTC. ... however: The 1st 210000 blocks each allow creating 50 BTC. The 2nd 210000 blocks each allow creating 25 BTC. The 3rd 210000 blocks each allow creating 12.5 BTC. ... The 10th 210000 blocks each allow creating 0.09765625 BTC. The 11th 210000 blocks each allow creating 0.04882812 BTC, and not 0.048828125 BTC, ...


45

Every block introduces 50 new coins in the system. This quantity (50) halves every 210,000 blocks. So, getting the limit of coins it is possible to generate is quite easy : it's the sum of a geometric series. Also, note that this is an upper bound ; the actual quantity will probably be a bit lower due to rounding issues (BTC has a finite number of decimals, ...


37

A pre-defined schedule limits the total number of bitcoins so that they gradually approach a total of 21 million (ignoring those that have been lost through deleted or misplaced wallet files). The limit of 21 million bitcoins is "hard-wired" in to the protocol, and there will never be more bitcoins than this:


27

If you were a miner, what are the steps you would take to create the extra (21,000,012.5th) bitcoin? Where in the source code is this exactly (link)? There are two components to CVE-2018-17144. There is a crash bug and an inflation bug. Both are triggered by almost the same scenario: a transaction contains an input multiple times. In general, how this ...


22

Assuming Bitcoin is still active at that point in time, mining will continue, because transaction fees will make it worthwhile to do so. This topic has been discussed heavily in other answers, including: What happens once the mining reward gets cut in half? How many bitcoins will there eventually be? How much will transaction fees eventually be? The last ...


21

There will definitely be a tragedy of the commons problem if things stand as they are now. This was discussed at some length here and elsewhere. There are some proposed ways to address this and make transaction fees nonzero (block size limit, hardcoded fees, insurance entities, mining cartel, gentleman's agreements which are maintained for fear defection ...


19

According to blockchain.info, the block 210000 was solved on 2012-11-28 15:24:38 GMT, and was relayed by Slush's Pool. The pool's Stats page also claims to have solved that block. It has also been stated that the block was solved by pool's user by the nickname of laughingbear.


18

Neither. The reward eventually ceases, but not at 21 million Bitcoins. Here's the code (edited for clarity and brevity): int halvings = nHeight / 210000; CAmount nSubsidy = 50 * COIN; // COIN is one Bitcoin // Subsidy is cut in half every 210,000 blocks which will occur approximately every 4 years. return nSubsidy >> halvings; (Source.) Note that ...


17

Mike Hearn just posted about how Network Assured Contracts handle this problem. I don't find an immediate flaw with this. This is how I understand the proposed solution: Anyone with an interest in a high hash rate (basically, anyone holding a large amount of coins), can initiate or cooperate on SIGHASH_ANYONECANPAY transactions. Those are an ...


16

It's not just about the miners, it is also about people using bitcoin. If miners decide to fork the chain and keep block bounty at 50btc, they cannot use those bitcoins in any place where people have not also modified their non-mining bitcoin client. Protocol changes are not just about >50% of miners, but about >50% of user clients. In this case, since ...


15

As Artefact2 mentioned, Bitcoin uses fixed-point math to calculate the block subsidies. So, ignoring the unspendable genesis block, the sundry lost coins and unclaimed rewards, the maximum number of bitcoins is 20999999.9769 BTC. I found that number through the following python program: COIN = 100 * 1000 * 1000 nSubsidy = 50 * COIN nHeight = 0 total = 0 ...


15

A single Bitcoin is currently divisible up to 8 decimal places (giving you 21*10^14 units of money, or about 2.1 quadrillion units), nothing stops it from being divided further with small protocol change. In order to change the limit of Bitcoins created, one needs to change the protocol and force most of the Bitcoin network to adopt the change, which can be ...


15

Bitcoin becomes very insecure if miners stop mining. Think of how easy a 51% attack would be to pull off. However, I disagree with your assumption that miners will stop. And certainly that if Bitcoin dies it would be because miners stop. I would instead think that miners would only stop if something else already killed Bitcoin. Bitcoin is designed to always ...


14

It's a complete irrelevancy. It is still early, and Bitcoins are worth on the order of $3 each. If you want to be an early adopter, buy Bitcoins now. If Bitcoins never become really valuable, what difference does it make whether it's fair or not? The sums involved will be modest. If Bitcoins ever do become really valuable, what difference does it make ...


14

Theoretically yes, but that moment is so far in the future it is likely that some other events such as new currency technology will surpass bitcoins. However, mining will not stop. Mining is the security backbone of bitcoin, and it will continue because it will still be profitable to mine. Miners will be paid fees from existing bitcoins with every ...


14

Every block has exactly one "coinbase transaction", the one transaction which doesn't have actual inputs, but gets all the fees and mining subsidy. Every 210000 blocks, this subsidy halves. Right now, each block is allowed (not required!) to bring 50.00000000 BTC into circulation. Very soon, this will become 25.00000000. Four years later, 12.50000000. And ...


13

I think you are confusing two things here: Block generation rate New bitcoins introduced per block Blocks will always be found at a rate of approximately one per 10 minute. The difficulty of finding a block adjusts itself according to how many people are trying. Simply said, if N people are mining (all with equal hashing power), they will each (on average)...


12

It is exactly at block 420000. When block 420000 will be mined is not certain, as the block mining process is random and influenced by hashrate variation.


11

A surge in transactions would mean a surge in transaction fees. So it does not follow that there would be a massive decline in mining. In any event, we have about a decade to work out what changes, if any, are needed. Nobody has a crystal ball. One interesting issue though -- right after a block is mined, all the 'juicy' transactions will be taken, and the ...


10

Every node in the Bitcoin network checks every block it receives and validates any transactions in it. As coin generation is a transaction that is included in the block, it is also checked. Same as a node would not accept a transaction that does not balance its inputs and outputs (for example, by spending more coins than it has), neither would it accept a ...


10

No, mining will not come to an end at that point. The article is incorrect. Mining will continue once the block rewards are no longer available, as transaction fees will continue to be offered. As the block rewards tend towards zero, the total value of transaction fees in each block will start to exceed the block reward. This will happen long before the ...


9

There will be 32 more if the precision doesn't increase. If Bitcoin lasts this long (very unlikely), precision probably will be increased.


9

Because the block halving incentives getting into Bitcoin NOW, rather than later. Early birds take more risks and get more rewards. Otherwise the network would have problems getting enough miners involved in the first place. Asides that, there is a concept of inflation and deflation - we have already experienced the first one, so we might as well try the ...


9

The Bitcoin reward schedule follows a predetermined pattern, see Controlled supply from the Bitcoin wiki. The next reward drop will happen at block number 420000. The current block number at the time of writing this answer is 318662. There are about 101338 blocks remaining. At approximately 10 minutes per block, there are approximately 1008 blocks per week, ...


8

According to a BIP (Bitcoin Improvement Proposal) I found, this code: nSubsidy >>= (nHeight / 210000); will actually wrap the reward generation back to 50 at some point in 2200 or so. Making the supply of bit coins infinite. The python code above does not have this property. The C++ code does. See BIP https://github.com/bitcoin/bips/blob/master/bip-...


8

Bitcoin was publicly announced before mining began. Those who were interested in cryptography and new digital technology were more likely than others to learn about it sooner, and it's perfectly fair that they were in a position to profit more from any rise in its value since its success would mean the information they were browsing had more value than the ...


8

I've read some of the linked discussions, and it seems some of the participants fail to understand the basic economic theory of the marginal cost. In any high fixed-capital business, the net present value (NPV) determines the ROI (IRR) and determines the opportunity cost where investors apply their capital. Thus, in normal functioning markets, the lowest ...


8

There are a lot of reasons and I don't think it's known what factors led to the final decision. For one thing, when the basic Bitcoin mechanics were designed, there was a significant risk that Bitcoin would never be adopted. By giving a fixed term to mining and a fixed supply of Bitcoins, the original designer(s) increased the chances that people would want ...


8

This is the announcement of Bitcoin: http://www.metzdowd.com/pipermail/cryptography/2009-January/014994.html Total circulation will be 21,000,000 coins. It'll be distributed to network nodes when they make blocks, with the amount cut in half every 4 years. first 4 years: 10,500,000 coins next 4 years: 5,250,000 coins next 4 years: 2,625,000 ...


Only top voted, non community-wiki answers of a minimum length are eligible