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Does my Bitcoin-Qt wallet backup file have "everything" I need (private key)?

I mean, is that the file I would copy and store offsite in case my house burns down? Does it have my private key encoded in there?

Peter Mortensen
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obelia
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2 Answers2

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Your bitcoin.dat file contains your private key(s) as well, however I would suggest you extract them now for the addresses that hold money (if any), if empty then it's not much of a use, unless you accept donations there or have a business set up to that address.

How to extract your private keys for addresses that hold at least some money:

  1. Go to Help > Debug > Console
  2. Unlock your wallet if it is encrypted by calling: walletpassphrase YOURPASSWORD
  3. Call listreceivedbyaddress to get all not-empty addresses
  4. For each of them call the dumpprivkey MYADDRESS
  5. Call walletlock once you're through to lock back your wallet
  • What is to be gained by going extracting the keys this way when they're encoded in the .dat file? I mean, do I really want to have these keys extracted and unencoded? – obelia Dec 28 '13 at 02:11
  • That is the safest way around. The safest wallet is no wallet at all. All you really need is your private keys. As for me, I have no wallet for my big account. It's all a matter of choice, after all. –  Dec 28 '13 at 02:33
  • but if the wallet is encrypted, isn't it safer than unencrypted keys? – obelia Dec 28 '13 at 02:37
  • All it takes for you to lose your bitcoins is a trojan that will upload your bitcoin.dat to the attacker and then record your keystrokes (keylogger) when your OS's focus is set to the bitcoin-qt.

    Keep your bitcoin.dat on a removable media that gets stolen or you forget somewhere and your passphrase is ridiculously easy to guess, voila, your coins are gone.

    On the other hand memorizing your (fat account's) key is only vulnerable to amnesia. If you can't memorize it, store it in a place that nobody knows what it is and what it's for and encrypt it with a password that you will remember.

     –  Dec 28 '13 at 04:26
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You only need to copy the wallet.dat to backup your private-keys. Do this while Bitcoin-Qt is not running. All other information will be deduced from the blockchain once you re-import the wallet.dat except any custom labels you have given to addresses.

Of course, if you encrypted the wallet.dat you will also have to remember the passphrase.

Murch
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  • So does the "Backup wallet..." menu item simply copy wallet.dat? – obelia Dec 28 '13 at 02:34
  • Oh, I was unaware that such a menu item had been introduced to Bitcoin-Qt. Now, from what I read it should be safe to use even while Bitcoin-Qt is running. (The manual copying of the wallet.dat should only be performed when Bitcoin-Qt is not running.) I would assume that it also just copies the wallet.dat, but I didn't find anything that specifically explained which files it stores. Will check it out later, going to be now though. – Murch Dec 28 '13 at 02:43
  • It's a litecoin-qt wallet - I just assumed it was the same as the bitcoin one. – obelia Dec 28 '13 at 03:10
  • The bitcoin-qt wallet also has "Backup Wallet..." menu option. – obelia Dec 28 '13 at 03:17