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10

I'm working on a Bitcoin project, and what I've seen are: Just the Bitcoin address A url parameter-like scheme with the format "bitcoin:{plus the bitcoin address}" (no brackets used) A more elaborate url parameter that includes the amount, like "bitcoin:{bitcoin addr}?amount={the amount} Coinbase uses the last scheme and it is fully recognized by the ...


9

You can't include the USD amount, but you certainly can include the btc amount in the QR code. The QR code essentially embeds a text like this: bitcoin:1ArmoryXcfq7TnCSuZa9fQjRYwJ4bkRKfv?amount=0.005 Note the amount here is the amount in BTC. You can generate a QR code for that text using gobitcoin.io. If you just want to insert an image, you can use ...


7

This is definitely a scam. Even if an activation fee was a legitimate thing, they would just charge that amount out of the amount you were going to receive - if you were to receive $1000 and the fee was $5, they'd just give you $995. Beyond that, no bank I'm aware of charges fees in cryptocurrencies. Don't send any money to these people.


5

As of November 2013, Bitcoin-qt generates a QR code. Click the Addresses button at the top of the window, highlight the wallet address you want, and then click the "Show QR Code" button at the bottom of the window. Add a message, if you want, or not, and then click the "Save As" button. It will be saved as a PNG image file.


4

The QR code is simply a convenient way of sharing an address, to avoid having to type it. It encodes exactly the same information as the alphanumeric address and provides no additional security. If you have another way of giving someone an address (e.g. sending it to them by email), there is no need to use a QR code at all. How the other person verifies ...


4

Use another wallet like green wallet or Mycelium and scan the QR code. Also, you can even verify the content of the QR with Google Lens, or another QR reading app.


3

I'm the founder of CryptoCoinJS and use the library for my own software. This is probably obvious, when scanning QR codes, check for both. When generating QR codes, for backup I'd just do the address and for payment requests, I'd use the URI scheme.


3

You generally don't publish your public keys, you give clients an address (which is usually computed from a public key, but not exactly the same). You can definitely put an address in a QRCode. Putting a logo in the QRCode doesn't change anything about that. Generally you'd put a "bitcoin:" URI in the QRCode. More information can be found in BIP21. Note ...


3

A QR code encoding… a payment request specific to some payment provider is subject to the specific payment provider's terms of use. A typical range could be between a few hours and a day. an on-chain Bitcoin address remains valid indefinitely. Although address reuse is not recommended, it could be used for multiple payments. a Lightning Invoice will be ...


3

Does a Bitcoin qr code become invalid after 1 Year? Generally no. A Bitcoin QR code encodes a Bitcoin address. These addresses are valid forever - in the sense that valid Bitcoin transactions can be created which pay to those addresses. So long as someone still knows the original private key (or master private key) for the address, any money sent using that ...


2

You can use any QR generator to create the image. Just select type "text", ECC level "H", and UTF-8 encoding. The QR codes are nothing more than the address. I use http://goqr.me/ for a quick online generator. Otherwise Mikael's link works well from what I've heard.


2

Do you want to just generate the QR code for one time use, or include the code generation into a program? If the latter you can use this for javascript: http://larsjung.de/qrcode/


2

That's a paper wallet. Search for that. bitaddress.org or paperwallet.com are examples. The way you intend to use it basically comes down to printing the private key part of a bitcoin wallet and giving that to someone else. Another use would be putting it in a safe so you can't get hacked.


2

Janina Lowisz of Bitnation's BlockchainID project became the first "World Citizen on the Blockchain" by making a sort of blockchain passport: Something similar could be done for identifying pets. For instructions on how she did it, see: https://github.com/MrChrisJ/World-Citizenship


2

that's not a bad idea in regards of doing business and distributing it to people. however, as far as I know, a single address is fine because the address itself is secured. the security flaw of a single address distributed will be - people can check the addresses on how good your business is doing. hehe. correct me if I'm wrong. Wishing you all the luck with ...


2

However it is possible to generate a bitcoin QR code with a given value in USD, but it is no use since high transaction fees and highly volatile nature of bitcoin. Still, you can use third party services like CoinGate which provides you a real time convertion of USD to almost all major crypto currencies. But CoinGate will show their own BTC address to ...


2

Unfortunately, that’s the hacker’s BTC address. There are way too many fake BTC QR generators nowadays, so the best way to do that is to ask your wallet to generate the QR for you (or use a well-known website).


2

Yes definitely a scam. Don't proceed further.


2

Use any software you normally use to create QR codes. Ask it to create QR for text bitcoin:<address>. That's all you need: a QR generation tool you trust.


1

Check out https://github.com/shesek/bitcoinuri. Make sure to read the warnings.


1

try resetting the cache on jaxx and let it re-sync, the coins should show up


1

Yes, if someone locates the paper wallet and is able to read the key on it, they can spend any BTC sent to that wallet. The wallet is secure if used correctly. Paper wallets are usually intended to be stored in a safe place, such as a literal safe or bank vault. They are not meant to be left on desks, dropped on the street, etc. Additionally, you could ...


1

The Ardor wallet uses the NRS.generateQRCode() function from nrs.server.js to generate a QR code based on string data into a target div. Both the data and the div reference are provided as parameters. This function relies on the qrcode.js library from the 3rdparty folder.


1

The address you have is a watch-only address, meaning you can only watch it, but not send it without the private key. The private key is something you HAVE TO have in order to send it. It's 32 bytes in size and starts with a 5


1

It's just for convenience. Make sure to d̶o̶u̶b̶l̶e̶ triple check and use a pen that's readable in ten years, too.


1

Just add amount parameter to QR data: bitcoin:1ArmoryXcfq7TnCSuZa9fQjRYwJ4bkRKfv?amount=0.005 use google chart to generate QR https://chart.googleapis.com/chart?chs=250x250&cht=qr&chl=bitcoin:1ArmoryXcfq7TnCSuZa9fQjRYwJ4bkRKfv?&amount=0.005 if you are asking about auto sending bitcoin through QR so it's not possible.


1

Yes, type it in. Or you can copy the address and email it to yourself and copy and paste it from the email. There really isn't any easy mechanism in Bitcoin for the person receiving the funds (i.e. your phone) to request the money from the person sending the funds (i.e. Coinbase). There is the BIP 70 payment protocol but that requires both a compatible ...


1

I found another Android app called "Bitcoin Wallet" that let me "sweep" the paper wallet into another address. Everything is fine.


1

The address validation script is actually from RosettaCode https://rosettacode.org/wiki/Bitcoin/address_validation#PHP All you need to do is create the new address and then put the address in a QR Code. You could use the Google Charts API <?php require_once("block_io.php"); $block_io = new BlockIo($apiKey, $pin, $version); $createAddress = $block_io-&...


1

https://nxtwiki.org/wiki/The_Nxt_API_Examples#Encode_QR_Code You can do the following: http://localhost:7876/nxt? requestType=encodeQRCode& qrCodeData=NXT-7A48-47JL-T7LD-D5FS3& width=100& height=100 Or via the command line: curl -d requestType=encodeQRCode -d qrCodeData=NXT-XXX-XXX-XXX-XXX -d width=100 -d height=100 http://localhost:...


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