QR codes and wallet public address

[bitty23]

Hello

A while ago I could enter my paper wallet 'share address' via a qr code onto a site which then told me how much I held on that wallet.
I think it was on Blockchaininfo/blockchain.com?

I cannot see where to do this on this site any more.

Is there anywhere I can use the share address on my wallet securely using the qr code? 

I can see some warnings against this but I am confused as surely the public address is secure to share?

I do not have a smart phone and use the cam on my computer.

Thanks.

[hosseinimr93]

Go to blockchair.com and click on "Scan QR-code of an address" button.

I can see some warnings against this but I am confused as surely the public address is secure to share?

Your bitcoin address can only be used for receiving bitcoin and checking the balance.

[masulum]

There are two kinds of keys in every crypto address, both bitcoin and altcoin, namely public keys and private keys. If you share a public key (aka Public address or wallet address) it is safe and there will be no threat of other people taking over your wallet.

It will be different if you share your private key, people who see the private key (aka secret key) that you have, they can open your wallet without having to know your address first.

Sharing QR or text for wallet address is safe. However, using one wallet address for all assets will make it easier for other people to know the amount of your assets. If you want to more safe, you can split your asset to some address. and make sure you have a backup of private key or seed phrase.

Using computer cam is works for scan QR too, sometimes i used my laptop cam to scan address, so no worry if you don't have smart phone, as far as you computer able to scan QR with you computer cam.

[Upgrade00]

Just to add, if you just wish to go completely offline, you do not have to use a block explorer like the one suggested above anytime you wish to check your balance, you can simply create a watch only wallet.

By the name, a watch only wallet only allows one to watch the wallet, but cannot be used to sign transactions. To set up;
• Download a reputable wallet software like electrum from the original website and verify the signature,
• Copy your xpub (master public key)
• import your wallet into electrum using the xpub
You can check your balance and previous transactions at anytime without your private key being online.

If you share a public key (aka Public address or wallet address) it is safe and there will be no threat of other people taking over your wallet.

The wallet address is a hash of the public key with some other components, they are not the exact same thing. Your public key is not revealed when receiving Bitcoins, but only when initiating a transaction.

[bitty23]

Thanks for those helpful answers. Unfortunately, Blockchair could not read my qr code via the inbuilt cam. Are there any other site where I can scan the code via the cam to check the balance? 

[jseverson]

Thanks for those helpful answers. Unfortunately, Blockchair could not read my qr code via the inbuilt cam. Are there any other site where I can scan the code via the cam to check the balance? 

I don't think this has anything to do with the service itself; any QR reader should be able to extract the text from your QR Code. Maybe your camera is the problem? Are you using a webcam?

Anyway, I'm assuming your QR Code contains your Bitcoin address, in which case, you only need to scan it with your phone (which is way easier than using a webcam assuming you're using one), copy the text, then paste it to your preferred block explorer like https://www.blockchain.com/explorer.

[20kevin20]

If the website doesn't see your camera or so, then first try to see whether your access to the camera is blocked by your browser. If it is, unblcok it. Otherwise.. if you're sure it's not blocked, then see if it works in other apps! If you're on Windows, try the Camera app and see if your cam is running.

A little extra tip: make sure you're scanning the public, not the private key.

[mersal]

Thanks for those helpful answers. Unfortunately, Blockchair could not read my qr code via the inbuilt cam. Are there any other site where I can scan the code via the cam to check the balance?  

Web cams even on the lastest laptops are not going to read those qr codes, either you need to buy an external hd webcam which may cost you $100 to huge price tags...

On the other side you can be a smartphone for less than $100 which is having 10 times better camera quality than a normal webcam.

[bitty23]

 I tried the blockchair site on another computer and the cam worked. So it must have been the previous machine. Once again, thanks to all for the suggestions.