How do coins get lost?

[yordan]

If coins are lost why can't they be discovered again by miners doing them same brute force computations necessary to discover them in the first place?

Is anybody keeping stats on "lost coins"?

[Mike Christ]

Coins become lost when the private keys to them aren't stored anywhere, and nobody is holding them.  So though the coins never really disappear, they can't be moved anywhere, because no one has the private keys required to move them.

[yordan]

Coins become lost when the private keys to them aren't stored anywhere, and nobody is holding them.  So though the coins never really disappear, they can't be moved anywhere, because no one has the private keys required to move them.

Can't the private keys be cracked the same way they are discovering new coins?

[odolvlobo]

If coins are lost why can't they be discovered again by miners doing them same brute force computations necessary to discover them in the first place?

Is anybody keeping stats on "lost coins"?

The process of mining is different from the process of finding a private key. It is much easier to mine bitcoins than to find a private key, and the word "much" here is a ridiculous understatement. The difficulty in cracking a private key is a fundamental attribute of bitcoin. It is close to impossible and that is what makes bitcoin secure.

There are statistics related to how long coins sit idle, but there is no way to know if coins are "lost" or not.

[lassdas]

why can't they be discovered again by miners doing them same brute force computations necessary to discover them in the first place?

New coins don't get discovered, they simply don't exist and are created.
Lost coins do exist, you can't create them again.

There's no way to know which (or how many) coins are lost, because they look just as any other coin,
there's no difference between lost coins, or coins that just haven't moved because they've been stored on an offline-wallet hidden in a vault for a couple of years/decades.

[jackjack]

Coins become lost when the private keys to them aren't stored anywhere, and nobody is holding them.  So though the coins never really disappear, they can't be moved anywhere, because no one has the private keys required to move them.

Can't the private keys be cracked the same way they are discovering new coins?

I wouldn't have to bruteforce 115792089237316195423570985008687907853269984665640564039457584007913129639936 possibilities

[Mike Christ]

Coins become lost when the private keys to them aren't stored anywhere, and nobody is holding them.  So though the coins never really disappear, they can't be moved anywhere, because no one has the private keys required to move them.

Can't the private keys be cracked the same way they are discovering new coins?

I wouldn't have to bruteforce 115792089237316195423570985008687907853269984665640564039457584007913129639936 possibilities

Have they invented -illion words for how much that is? 

[hybrid]

Coins become lost when the private keys to them aren't stored anywhere, and nobody is holding them.  So though the coins never really disappear, they can't be moved anywhere, because no one has the private keys required to move them.

Can't the private keys be cracked the same way they are discovering new coins?

I wouldn't have to bruteforce 115792089237316195423570985008687907853269984665640564039457584007913129639936 possibilities

Have they invented -illion words for how much that is? 

115 quattuorvigintillion, 792 trevigintillion, 89 duovigintillion, 237 unvigintillion, 316 vigintillion, 195 novemdecillion, 423 octodecillion, 570 septendecillion, 985 sexdecillion, 8 quindecillion, 687 quattuordecillion, 907 tredecillion, 853 duodecillion, 269 undecillion, 984 decillion, 665 nonillion, 640 octillion, 564 septillion, 39 sextillion, 457 quintillion, 584 quadrillion, 7 trillion, 913 billion, 129 million, 639 thousand and 936 

[Mike Christ]

Coins become lost when the private keys to them aren't stored anywhere, and nobody is holding them.  So though the coins never really disappear, they can't be moved anywhere, because no one has the private keys required to move them.

Can't the private keys be cracked the same way they are discovering new coins?

I wouldn't have to bruteforce 115792089237316195423570985008687907853269984665640564039457584007913129639936 possibilities

Have they invented -illion words for how much that is? 

115 quattuorvigintillion, 792 trevigintillion, 89 duovigintillion, 237 unvigintillion, 316 vigintillion, 195 novemdecillion, 423 octodecillion, 570 septendecillion, 985 sexdecillion, 8 quindecillion, 687 quattuordecillion, 907 tredecillion, 853 duodecillion, 269 undecillion, 984 decillion, 665 nonillion, 640 octillion, 564 septillion, 39 sextillion, 457 quintillion, 584 quadrillion, 7 trillion, 913 billion, 129 million, 639 thousand and 936 

Talk about a mouthfull

[yordan]

I see 

[Gator-hex]

Lost because they deleted their wallet.dat file somehow

keep a backup

[WeTradeCoins]

Coins become lost when the private keys to them aren't stored anywhere, and nobody is holding them.  So though the coins never really disappear, they can't be moved anywhere, because no one has the private keys required to move them.

Can't the private keys be cracked the same way they are discovering new coins?

I wouldn't have to bruteforce 115792089237316195423570985008687907853269984665640564039457584007913129639936 possibilities

Have they invented -illion words for how much that is? 

115 quattuorvigintillion, 792 trevigintillion, 89 duovigintillion, 237 unvigintillion, 316 vigintillion, 195 novemdecillion, 423 octodecillion, 570 septendecillion, 985 sexdecillion, 8 quindecillion, 687 quattuordecillion, 907 tredecillion, 853 duodecillion, 269 undecillion, 984 decillion, 665 nonillion, 640 octillion, 564 septillion, 39 sextillion, 457 quintillion, 584 quadrillion, 7 trillion, 913 billion, 129 million, 639 thousand and 936 

+1 and respect. haha! 

[jackjack]

Coins become lost when the private keys to them aren't stored anywhere, and nobody is holding them.  So though the coins never really disappear, they can't be moved anywhere, because no one has the private keys required to move them.

Can't the private keys be cracked the same way they are discovering new coins?

I wouldn't have to bruteforce 115792089237316195423570985008687907853269984665640564039457584007913129639936 possibilities

Have they invented -illion words for how much that is? 

115 quattuorvigintillion, 792 trevigintillion, 89 duovigintillion, 237 unvigintillion, 316 vigintillion, 195 novemdecillion, 423 octodecillion, 570 septendecillion, 985 sexdecillion, 8 quindecillion, 687 quattuordecillion, 907 tredecillion, 853 duodecillion, 269 undecillion, 984 decillion, 665 nonillion, 640 octillion, 564 septillion, 39 sextillion, 457 quintillion, 584 quadrillion, 7 trillion, 913 billion, 129 million, 639 thousand and 936 

I smell Wolfram Alpha 

[DannyHamilton]

Coins become lost when the private keys to them aren't stored anywhere, and nobody is holding them.
- snip -

There are actually two types of "lost coins".

If someone loses the private key associated with a bitcoin address, any bitcoins ever received at that address will remain unspendable (assuming that no weaknesses are ever discovered in ECDSA, SHA-256, and RIPEMD-160 in the future).  However, if someone finds that private key (maybe it was written on a piece of paper that was dropped, but then later found by someone else?) all bitcoins associated with that address immediately become spendable again.  In most cases of "lost" bitcoins, the private key was ONLY stored in a file on a computer, and that file is deleted, or destroyed, making it essentially impossible for anyone to ever "find" that private key in the future.

The other type of "lost" coin is very rare and can be identified on the blockchain.  These coins are permanently lost, and there is no way to recover them.  They cannot be recovered if ECDSA, SHA-256, and/or RIPEMD-160 are broken in the future.  They cannot be recovered under any circumstances.  This type of "lost" coin involves someone paying a transaction fee on their transaction, and a miner having a bug in their software that causes them not to claim that transaction fee in their reward.  The fee is paid, but since nobody claimed it, it simply ceases to exist.

[SilverBull]

I had lost a wallet.dat file, I formatted the wrong drive.

I ran a tool to search the block device for a string I knew would be in the wallet.dat. I was able to recover the keys several months after my mistake.

[WeTradeCoins]

I had lost a wallet.dat file, I formatted the wrong drive.

I ran a tool to search the block device for a string I knew would be in the wallet.dat. I was able to recover the keys several months after my mistake.

How many coins you had in the wallet?

[frga13]

115 quattuorvigintillion, 792 trevigintillion, 89 duovigintillion, 237 unvigintillion, 316 vigintillion, 195 novemdecillion, 423 octodecillion, 570 septendecillion, 985 sexdecillion, 8 quindecillion, 687 quattuordecillion, 907 tredecillion, 853 duodecillion, 269 undecillion, 984 decillion, 665 nonillion, 640 octillion, 564 septillion, 39 sextillion, 457 quintillion, 584 quadrillion, 7 trillion, 913 billion, 129 million, 639 thousand and 936 

OMG great!

[giraffe]

when people pass away I think