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I transfered a small amount of btc from my private wallet with bitcoin core client. When I check blockchain.info I see the transaction with the amount of btc i transferred going to the correct address. But I also see the rest of the BTC in my wallet going to an unknown address.

Is it supposed to do this, or have I been hacked?

marked as duplicate by Murch May 14 '18 at 19:45

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  • Reading up a bit I now understand that what happened is that the client had to make a change-transaction since the only incoming transactions to my wallet doesn't match what im trying to send out. It would be nice if the client could inform you about this and also show your change-address(es). – Frank Dec 8 '17 at 9:21

I'm 99.9% sure the 'unknown' address is the 'change address' of your wallet, being returned back to your wallet. If you check the balance of your wallet, is it what you think it should be?

You should read this: http://support.exodus.io/article/109-what-are-bitcoin-change-addresses

  • After reading up a bit, I came to the same conclusion. The balance in my wallet is correct, but my original fear was that this would change after the transaction got confirmed. Is there any way to confirm that the address actually is the 'change address'? – Frank Dec 8 '17 at 11:02

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