Some people don't know much about sweeping and importing and when to either import or export their private keys. So I just decided to make a topic with a simple explanation of what these two procedures are and under what circumstances one could attempt to do one over the other.
IMPORTING A PRIVATE KEY
Importing a private key from an already existing Online or software or paper wallet to another software wallet such as Electrum, Armory, Mycelium or Coinomi implies that you are moving that private key into the new wallet's existing collection of keys.
In this case, If any coins were in the address before you imported its private keys, they will be visible and accessible from both the old wallet from which the keys were exported from and the new wallet to which the keys have been imported.
After importing, the new software wallet will be like a replica or copy of your original wallet.
PROS • It's quick, the whole process of exporting and importing the wallet can be done in a very short time if one knows what they are doing.
• No fees needed at all as it does not involve any form of transaction.
CONS • If the original paper wallets private keys get compromised or if someone else ever has a copy of the paper wallet's Private keys, It means s/he can still be able to spend your coins even after importing them to a new wallet.
• It distorts your new wallet backup especially with
Deterministic wallets (
wallets where seed phrases are used for restoring the addresses in them such as electrum). This means after every private key import you make, you will need to redo a backup procedure.
CAUTION⚠️Once you have imported a private key of your paper wallet to the new software wallet, It's very important you make an immediate backup even if you don't plan to use the new software wallet/hot wallet for a long time.
This is because if you make a bitcoin transaction, even for a small amount, the whole bitcoin amount will be spent and the change will be sent back to your wallet but to one of the new addresses in it and not your original paper wallet address that you imported.
i.e. You have imported a private key of your paper wallet that has some bitcoins say 10 BTC to a new software wallet. Afterwards you then do online shopping and decide to spend 2 BTC. What you have to note is that even if you want to spend only 2 BTC, the entire amount of 10 BTC in your address will be spent during the bitcoin transaction and the change (in this case 8 BTC) will be sent back to a new address which has a different PK but in the same wallet.
This will make the original address(Paper wallet) empty. Therefore, if you delete the software wallet (hot wallet) without backing it up. It means you lose all your BTC that was sent to the new address as you will have no other way of recovering the wallet.
SOLUTION TO AVOID LOSING COINS- Back up the new wallet as soon as you are done importing.
- Resend the change back to paper wallet address before deleting the software wallet (but in this case your privacy will be compromised). Sending it to a new paper wallet address is very advisable.
Note: This caution should be taken into very serious consideration if you are going to make transactions from your new software wallet and plan to use the paper wallet storage method afterwards or you risk losing your bitcoins.SWEEPING PRIVATE KEYS
When sweeping a paper wallet or private keys to a software wallet, you are essentially creating a new transaction to a new public address which empties your original wallet i.e. paper wallet.
This means after the sweeping process, your coins will be sent to a new public address of your software wallet which will now have a new private key that is stored in an encrypted form on your device.
As it is like making a transaction on the blockchain to a new address, a relevant transaction fee will be deducted from your whole balance and rest of the amount sent to your new wallet.
Also, unlike in the case of importing, after a sweep, your coins will be accessible and visible only from the new software wallet to which you have swept your private keys
PROS • Your new wallet's Recovery seeds won’t be broken due to the sweeping procedure meaning you can easily recover your wallet using the seed phrases you used for creating it without any issues.
• It’s safer in case your original paper wallet gets compromised. New wallet address after sweeping means at that time you will be the only one who knows your private keys.
CONS • You will need to cover a transaction fee in order to carry out the procedure.
• You have to wait for the transactions to get confirmed in order to have the whole process completed… Could be slow according to network congestion and fees.
WHEN TO SWEEP OR IMPORT PRIVATE KEYS
• It’s very important you import your private keys ONLY when nobody else knows them apart from you.
• If you ever have even any single feeling that your Private keys could have leaked or someone could be having a copy of them. The best thing to do is to sweep your wallet.
• You can also sweep your private keys if you want to take all your coins to a new address and destroy the paper wallet.
• Also, it’s important to note that if you used to receive periodic payments on your old paper wallet before you did the sweeping, payments will still continue going into the old address and not the new wallet address. This means you will either have to manually keep re-sending the coins to the new wallet or simply change the periodic payment details to your new wallet's public address. In-case your private key has never been compromised. Importing your wallet is the most reasonable thing to do here.
SWEEPING? WHY NOT JUST SEND MY COINS TO A NEW ADDRESS I OWN?
Sweeping and sending are actually the same thing, The only small difference is that with sweeping, you are looking at making a transaction which may sometimes involve lots of small inputs.
This is because certain wallets generate so many addresses for security and privacy purposes so that your transactions and expenditure cannot be easily tracked. So in this case, as time goes on your different address could have different small unspent coins(balances). Sending them to your new wallet address could prove challenging and even impossible but with sweeping, you could easily send all your small unspent coins to a new address with less hustle.
WALLETS THAT SUPPORT IMPORTING AND SWEEPING
• Ledger Nano S
• Trezor
• Exodus
• Bitcoin Core
• Electrum
• Jaxx’s Chrome Extension
• Mycelium
• Coinomi
• MyEtherWallet
• MetaMask
• Coinomi
• Mycelium
• Armory
UPDATE* Caution section added thanks to
LoyceV* Russian Translation by
madnessteat ➖
Импopт или cвипинг пpивaтныx ключeй* Indonesian Translation by
ryzaadit ➖
[EDUKASI] Importing Private Key vs Sweeping Private Key | Mana yang lebih baik?* Nigerian (Naija) Translation by
Chilwell ➖
Importing Vs Sweeping Private Keys; Wetin you need to know.Any other possible additions and suggestions are welcome,
Thank you.
Sources and Reference:
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Private Keys: Import vs. Sweep-
Highlighting The Difference Between Sweeping & Importing Private Keys-
Sweep VS Send?-
Bitcoin Wiki