How many Bitcoins are lost forever?

[Bitcoinpro]

50 million

[ThEmporium]

That is an interesting question but unfortunately there is no way to ever know.  I am sure a lot of people got in at the beginning and became bored of it and just left or forgot about their wallets.  If only they could be recovered and distrubted to all!    That would be sweet!

Imagine, What if those wallet are still being registered in their names and those bitcoins are unused, did you hear any such methods that any responsible authorities from Bitcoin who take care of these things and safeguard those forgetten bitcoin accounts and return to them safely ?

[Argwai96]

Satoshi's addresses are unique and easily distinguishable from other addresses because he never combined his mined coins into a few large addresses in the same way other early miners did. Since he was also pretty much the only person mining throughout most of 2009 (apart from Hal Finney who mined alongside him for a brief period), almost all of the coins that comprise his massive stash are spread out across thousands of addresses containing 50 BTC that have all since remained untouched.

For example, this is probably one of Satoshi's addresses:

https://blockchain.info/address/15ubjFzmWVvj3TqcpJ1bSsb8joJ6gF6dZa

if he indeed sold those coin, he sold them at the 1200 peak, seeing how he was a firmly believer, still there is chance that he lost all those 1M coins, which would be a good thing, not for him maybe...

It's unlikely that he sold his coins since they haven't been moved on the blockchain. The only way he could have sold them while still remaining undetected would be if he sold the private keys to these addresses instead.

Thanks, well at lease we know there is a lot of this wallets around that he never touch and is ever going to sell, there are some crazy wallets out there and it actually fun to see the movement on the blockchain of so much money, is like standing on the traffic lane of a highway of money, something you cant do we the banking sector of course.

[Acidyo]

I would guess and say about 20% of the BITCOIN supply is lost forever.

[saturn643]

There is no way to estimate percentage of lost coins though. Coins haven't been moved for months or years could still be owned by someone.

[jeannemadrigal2]

There is no way to estimate percentage of lost coins though. Coins haven't been moved for months or years could still be owned by someone.

I was thinking exactly this.  It would not be unusual for someone to sit on a pile of them and wait for the value to go up.  I read an article that said if 15% of people in the world used bitcoin, then they would be worth 500k each.  Now, I know this number is far fetched and not something to count on, but the point is that many people believe that the value of them will go up a lot in the future, so they will sit on them.

[cakir]

You guyz are killing me.
All generated bitcoins are sitting on blockchain. None of them is lost!
People may loose their control over private keys (which is required to say "Hey, those bitcoins are mine"). That doesn't mean those bitcoins are lost forever.

How to loose bitcoins forever?
If you manage to delete some blocks from all of the full nodes; then yes we may say some of bitcoins are lost. But no, you can't do that. There're lots of offline computers which have entire blockchain. You can try to delete but you'll fail and we can recover it.

You're arguing this question: "How many bitcoins are not controlled by people?" or "How many people lost their control over their private keys? (and how many bitcoin balances are affected on those keys?)"
And the answer is "Unknown" (You can't know that). 

Also those controls can be regained by same people or others.

In conclusion; none of the bitcoins are lost. They're on the network.

[MCHouston]

You guyz are killing me.
All generated bitcoins are sitting on blockchain. None of them is lost!
People may loose their control over private keys (which is required to say "Hey, those bitcoins are mine"). That doesn't mean those bitcoins are lost forever.

How to loose bitcoins forever?
If you manage to delete some blocks from all of the full nodes; then yes we may say some of bitcoins are lost. But no, you can't do that. There're lots of offline computers which have entire blockchain. You can try to delete but you'll fail and we can recover it.

You're arguing this question: "How many bitcoins are not controlled by people?" or "How many people lost their control over their private keys? (and how many bitcoin balances are affected on those keys?)"
And the answer is "Unknown" (You can't know that). 

Also those controls can be regained by same people or others.

In conclusion; none of the bitcoins are lost. They're on the network.

I would say you are kind of right but when a private key is lost, the bitcoins on that private key are basically stuck and can never be used.  So for most practical purposes they are lost cause they can never be used or moved again.

[knowhow]

that is the same thing that have the key who won 100milion dollars and didnt regist it soo it would be yours but isnt because you did paid to regist it,about wallets well some bitcoins is lost really ,some left the bitcoin and deleted all with some satoshis inside them ,besides that some people lost them on hardisks on cpu computer well some is lost  but well as i said know that have them and doesnt know keys to moove them is like be dead bitcoin

[cryptworld]

We could actually make some estimations based on forum comments and news,but there is a fraction that it can't be known because it must be people who has forgot about it

I think there are hunred thousands of lost bitcoins

[Scream]

The logical conclusion is that each of these was an address setup by a miner in the first 2 years of the digital currency. The reward was paid into that address and no currency was ever added to it.

[wywoc1]

I think there are 20% percent of Bitcoin lost forever.

[pooya87]

I think there are 20% percent of Bitcoin lost forever.

there are 14.3 million bitcoin in circulation right now so 20% is equal to 2860000BTC
you are claiming that there are 686 million dollar worth of bitcoin lost?

care to explain why you think that?

[lolxxxx]

I think there are 20% percent of Bitcoin lost forever.

there are 14.3 million bitcoin in circulation right now so 20% is equal to 2860000BTC
you are claiming that there are 686 million dollar worth of bitcoin lost?

care to explain why you think that?

you are claiming that there are 686 million dollar worth of bitcoin lost?

I guess yes ... I have heard somewhere but i forgot the link i,ll update this post whenever i found it again .

Also whatever the amount of btc is lost forever why are we talking , thinking about it ? we cannot hack or get the bitcoins from the address or we ? Well actually my self i cannot hack ..

[Amph]

I think there are 20% percent of Bitcoin lost forever.

there are 14.3 million bitcoin in circulation right now so 20% is equal to 2860000BTC
you are claiming that there are 686 million dollar worth of bitcoin lost?

care to explain why you think that?

i don't know it seems a bit random, but if you look at this http://www.theguardian.com/technology/2013/nov/27/hard-drive-bitcoin-landfill-site

he only lost 7500, and it was a big lost already, but still tiny in comparison to 20% of the toal coins

i'm guessing if someone lost more than that, he would have revealed it like this guy did(but there aren't any other major news of many coins being lost), so the overall estimate of coin lost, it is very overrated i believe...

[JarvisTechnology]

I know it is a tricky question. What do you think, how many Bitcoins are lost forever and are 'out of the network' by lost private keys?

As per my internet search ,it has been come to a round figure of $5 bitcoins have lost or stolen . 
Bitcoins are crytocurrency uses SHA-256 algorithm which uses Private key to protect bitcoin.Private key is stored(kept)by user (bitcoin holder).
once stolen cannot be recovered.

[extrabyte]

people have guesses, but there is no way to know for sure ,lot of bitcoins where lost in 2009-2010 when people formatted their drives .As the value goes up people are being more careful with their coins.

[jones techbit]

A lot of these are lost wallets. Tons of early miners/adopters lost their computers/HDD with their wallets on them.

[Clint]

I don't think there's a way for us ever to find out, to be honest with you. But I really like to know though.

[pooya87]

I guess yes ... I have heard somewhere but i forgot the link i,ll update this post whenever i found it again .

the 20% that wywoc1 looks so random to me that is why i asked him. i am curious to see the link that you talking about. but still 20% looks so random to me :/

Also whatever the amount of btc is lost forever why are we talking , thinking about it ? we cannot hack or get the bitcoins from the address or we ? Well actually my self i cannot hack ..

i think it is more of curiosity rather than wanting to hack those addresses, which is impossible unless it is a wallet on a website like blockchain.info that you can hack the password to the wallet there but you can not hack private keys.