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Questions tagged [qrcode]

A kind of two-dimensional barcode that can be scanned by many smartphones. They can be used to encode URLs or Bitcoin addresses.

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16 votes
1 answer
1k views

Given a private key, how do you get a public address [duplicate]

Possible Duplicate: How are public & private keys in an address created? I am scanning in a private key from a QR code in an app I am writting to handle the import of physical bitcoins. ...
RobKohr's user avatar
  • 622
11 votes
7 answers
1k views

What additional benefits can QR codes bring to Bitcoin applications beyond payment requests?

Anyone who has recently used one of the Bitcoin wallets on a mobile device (and some desktop clients) will have seen a Bitcoin QR code. Clearly, QR codes allow for a succinct method for transferring ...
Gary's user avatar
  • 7,593
10 votes
2 answers
2k views

Using QR codes for bitcoin giveaway

Suppose I wanted to have a bitcoin treasure hunt, where QR codes were used. The first person who scanned a given QR code should receive some preset amount of bitcoins. Is this possible? (Preferably ...
lemonginger's user avatar
  • 5,432
8 votes
4 answers
51k views

What are QR codes and How do you use them as request payment from Wallet?

What are QR codes ? How do you use the QR code for payment function on the wallet ? When would you use it ?
BitCoin New Guy's user avatar
6 votes
6 answers
19k views

Generating a Bitcoin Address QR code with current USD price embedded?

I'm creating a Bitcoin QR link with my website, but I want to be able to just link to a page that generates the QR code with the current USD price equivalent of BTC in the QR. I tried blockchain.info, ...
Patoshi パトシ's user avatar
5 votes
4 answers
9k views

Bitcoin QR codes: raw address or Bitcoin URI scheme

I am the author of bitcoinaddress.js library and I am wondering what's the best content for Bitcoin QR codes. What Bitcoin QR codes should contain (for mobile wallet apps and other barcode scanners): ...
Mikko Ohtamaa's user avatar
4 votes
2 answers
6k views

Is there an Android app that will scan a QR code and show the balance?

What I'm looking for is an app that lets a person scan a QR code containing a Bitcoin address and then see the balance and transaction history for that address. For a specific use case, a mobile ...
Stephen Gornick's user avatar
3 votes
2 answers
859 views

Lightning Invoice QR-Code minimum size/display resolution?

what would be the minimum screen size to display lightning invoices as a qr-code? For the Raspberry Pi Zero I found these displays: 128x128 pixel LCD display (1.44 inch) 200x200 pixel e-paper/e-Ink ...
Jon Doe's user avatar
  • 31
2 votes
3 answers
2k views

How do you generate a QR code for a not so popular coin?

I'm running a the datacoin-qt client and was wondering how do you generate a QR code? This is relatively a new coin and I can generate an address, but I'm not sure where I can goto to generate a QR ...
Patoshi パトシ's user avatar
2 votes
3 answers
739 views

How can I securely create a QR code from a bitcoin address?

My Problem I am trying to generate a QR code for a public bitcoin address, preferably using command-line tools. The process poses a security risk because malicious software can generate a QR code that ...
Adam Matan's user avatar
2 votes
1 answer
76 views

QR to pay more than one address?

I know that I can generate syntax for a payment qr code like so: bitcoin:xxxaddressxxx?lable=reason&amount=0.051 this pays (to) 1 address! I however, would like to know if I can scan a QR that ...
Ben Muircroft's user avatar
2 votes
2 answers
618 views

Do I need an app and internet on my smartphone to enable a Lamassu ATM to detect and scan my QR code?

I want to send bitcoins to a friend through a Lamassu ATM. She has emailed me her request QR code and when I went to the Lamassu ATM point, after pressing on the start button and showing the QR code ...
pearl's user avatar
  • 131
2 votes
2 answers
3k views

Scanning QR codes with Electrum 3.0.1

When trying to scan QR codes with Electrum 3.0.1 it asks for zbar software. I'm not sure which one to download as some of them might be unsafe. Which Zbar QR scanner should we download?
Patoshi パトシ's user avatar
2 votes
0 answers
1k views

QR code on my phone looks different

I just set up a personal wallet, and the QR code on my phone, looks different from the QR code that blockchain.info shows. When I scan, the code on blockchain.info, I get the same address. I thought ...
j0h's user avatar
  • 153
2 votes
2 answers
2k views

How do I spend a paper wallet into my coinbase.com account using the Android Coinbase app and the paper wallet QR code?

I created a paper wallet using bitaddress.org and spent bitcoins into it using the Coinbase mobile (Android App). I then noticed that the paper wallet cut off part of the private key during printing! ...
Walt Howard's user avatar
1 vote
2 answers
603 views

How to test my Bitcoin QR code without giving my bank account

I set up a QR code on my website to receive Bitcoin payments. So now I need to test it. I thought that if I install a Coinbase app it would let me scan it with its QR code scanner to see how my QR ...
c00000fd's user avatar
  • 121
1 vote
2 answers
47 views

Where is a good source of information for procedural algorithm to program my own Bitcoin QR code generator?

Not trusting those already available QR code generators available, I would want to program my own. The idea is to input a Bitcoin key ( private or public ) and the program would simply generate the ...
Fred Cailloux's user avatar
1 vote
1 answer
741 views

Whats the use of QR-codes during wallet to wallet transfer?

I want to know hen the QR-code scanning actually takes place. For instance, if I send my wallet address to someone, how does the person verify that the sender is me, and what do I need to do as soon ...
8SINS's user avatar
  • 111
1 vote
1 answer
401 views

Does a Bitcoin qr code become invalid after 1 Year?

I have been trying to figure out if there exist a software which preserves a BTC QR code for more than one year.
Pettun Perl's user avatar
1 vote
1 answer
64 views

QR code life span

Once the QR code is generated, how long is the code good for 24 hours, 48 hours? I googled for the answer with no success. Thank you
Diann Jenkins's user avatar
1 vote
1 answer
272 views

How to gift an entire BTC wallet via QR code?

I have a unique scenario where I'd like to: Create a BTC wallet and add a small amount of funds to it. Generate a QR code that contains the private key. Then gift that QR code to a friend so they can ...
Rob's user avatar
  • 13
1 vote
1 answer
186 views

Is it secure to put a wallet address on one's business cards as a QR code?

As a company, we're making business cards, and would like to put our bitcoin addresses on our business cards as QR codes. Yet, I know that it is a best practice for wallets to cycle addresses - I mean,...
J. Doe's user avatar
  • 11
1 vote
1 answer
403 views

How do you generate a qr code for a new address and check for incoming payments from the command line?

Which one do you recommend for this Command line to generate QR-Code + address for requesting money Command line to check if the above has been received I don't want to install too many versions of ...
Bitcoin Digger's user avatar
1 vote
1 answer
76 views

How can I generate the qrcode client-side that would be compatible with the Ardor Wallet qrcode

I'd like to generate a qrcode the same way the Ardor Wallet generates it, such that it would be compatible. I found qrcode related javascript shipped with the Ardor node download in ardor/html/www/js/...
Mal Nemark's user avatar
1 vote
1 answer
757 views

How to put QR Code whenever I generate a unique address? block.io API

Hi guys as the title says. how can I generate a QR code whenever the block_io.php generates a unique address? I seem to have a problem when calling $newAddressInfo or $newAddressInfo->data->address ...
PPY XIII's user avatar
  • 116
1 vote
1 answer
143 views

First time buyer, questions before I screw up

I am wanting to buy BTC to buy goods but things are a bit confusing to me. First off, would I be better off buying from someone or a website, or use an atm? Once I purchase the BTC what is the best ...
BK82786's user avatar
  • 11
1 vote
1 answer
652 views

How to scan QR code with multibit wallet application?

I downloaded the multibit application for windows and was wondering if there was a way to scan a QR code with my webcam? If so where do I click because I dont see an option and no way am I going to ...
Patoshi パトシ's user avatar
1 vote
1 answer
924 views

Which mobile apps allow me to redeem a private key from a QR code?

Which mobile apps will let me scan a QR code of a private key (such as the one created by BitAddress) and then spend the funds from that coin? Please specify Android, iPhone (iOS), etc.
Stephen Gornick's user avatar
1 vote
1 answer
24 views

Is it possible to generate lightning address / invoice that can be used multiple times?

I'm planning to attend art exhibition, displaying some of my pieces, it's actually for the 🍕 coming soon. I can easily print QR code with my on-chain BTC address. I would like to print QR code with ...
Mars Robertson's user avatar
1 vote
0 answers
74 views

Message signing with airgapped wallet that doesn't support it

I need to implement message signing for various HWs, many of them support it on a firmware level, but some airgapped wallets like SeedSigner or Jade still don't. I was wondering if there's a way to ...
beefgroin's user avatar
1 vote
0 answers
28 views

Prepare transaction with multiple recipient

Do you think it is possible programmatically prepare a Bitcoin transaction that has multiple recipient to send the amount to? Do you think I can show this trasaction in QR code, so payer can scan it ...
János's user avatar
  • 388
1 vote
0 answers
422 views

block.io + scan generated QR code

So i created a block.io account and playing around with bitcoin address generation, as well QR codes. My source code for generating a new bitcoin address is that one: include_once("payment/block_io/...
vlzvl's user avatar
  • 109
0 votes
2 answers
971 views

Is it fraud? Would banks ask for fees through bitcoin?

So a man came to me on Instagram saying that he wanted to buy old money specifically from Hong Kong for a museum in Philadelphia, and that he would pay me good money for my old coins and bills, then ...
Anonymous's user avatar
0 votes
1 answer
44 views

Can I print my public key using a custom logo?

qrycode monkey allows me to print a qr code with my company's logo in the middle. Q: Can I do the same for our public key?
Phillip Senn's user avatar
0 votes
1 answer
945 views

Is BTCFrog bitcoin QR code generator hacked?

The following URL is self explanatory. It is trying to generate a QR code requesting 0.005BTC at the shown address http://www.btcfrog.com/qr/bitcoinPNG3.php?address=31oLAAQDmuRAGfkviHPDXFgV15To4idott&...
Fakeer's user avatar
  • 111
0 votes
1 answer
334 views

Dog identifier in blockchain

I would like to print qr-code with transaction that contains my home address to print it for my dog's necklace. If dog will get lost everyone can scan it and get the address. How can I prepare the ...
Sebastian Xawery Wiśniowiecki's user avatar
0 votes
2 answers
4k views

Bitcoin transfer through QR codes

Ok, so let's say I have a wallet with 1 BTC in it. Is it possible to transfer that balance to a QR code or some type of barcode? I want to know if it's possible to basically print out a piece of ...
user3038431's user avatar
0 votes
2 answers
95 views

Electrum's custom Base43 - looking for a 2-way deterministic hex converter

I am looking for a tool, suitable for an amnesiac offline air-gapped Linux Live host that will deterministically convert in both directions, between raw hex and Electrum's custom Base43 format, used ...
HansBKK's user avatar
  • 423
0 votes
1 answer
194 views

QR Scan "Unrecognized format" mycelium "Mastering Bitcoin'

Noobie here. In Ch. 2 of Antonopoulos' "Mastering Bitcoin", I try to scan figure 2-2 (per his instruction) using a recently installed Mycelium on my Android. Why do I keep getting "Unrecognized ...
JDOaktown's user avatar
  • 206
0 votes
1 answer
103 views

Bitcoin QR code on a product sold in stores [closed]

How and which company do i turn to implement a QR code for bitcoin on a product sold within stores.
ModelBTC's user avatar
0 votes
1 answer
204 views

Sent BTC to Jaxx Wallet Never Received [closed]

A friend suggested I use Jaxx Wallet so I downloaded the software and sent my BTC using their QR Code from Coinbase. Looking back, I should've left it where it was! It never arrived. I also sent LTC ...
qsunflower's user avatar
0 votes
1 answer
93 views

Use of Bitcoin paper wallet

A Bitcoin paper wallet contains a pair keys: public key (address used to receive coins) and private key (allows to spend coins stored at that address). Those keys are printed in a form of QR-codes so ...
Questioner's user avatar
  • 1,151
0 votes
1 answer
161 views

Wants to send my bitcoin to another wallet

I’m having issues trying to send my bitcoin to another wallet...it been asking me to confirm a whr code which I don’t really understand cos I have enough money on my wallet
user78438's user avatar
0 votes
1 answer
190 views

Are QR codes on paper wallets necessary

I don't have a wireless printer so I'm thinking about writing down the keys by hand on pieces of paper. Obviously I can't copy the QR codes that way. Are they necessary or do they just exist just for ...
user1691278's user avatar
0 votes
2 answers
4k views

Possible to transfer BTC via QR code?

Is it possible to embed an amount of BTC in a QR code to transfer to whoever scans it? E.g. I create a QR code for .5 BTC from my wallet, send the QR code to someone (without knowing their BTC wallet ...
ljenkins's user avatar
0 votes
1 answer
763 views

How do I transfer BTC from my Coinbase account to my Android wallet?

When sending BTC (funds) from the Coinbase website, it asks for a bitcoin address to which to send it. What is one supposed to do, type it in? What I would like to do is display a QR code in my ...
Tom Russell's user avatar
0 votes
1 answer
278 views

Generating a QR code using the NXT / Ardor api for scanning

Currently the nxt gui generates a QR code for certain pages where you can scan with your phone or another computer to do an air gap transaction. How can you do this via the api?
Patoshi パトシ's user avatar
0 votes
2 answers
1k views

Generate QR Code tesnet

I would like to generate a bitcoin paper testnet wallet. A paper wallet is a QR code of a private key and a QR code of a bitcoin testnet address, I assume it can be generate juste like this link does :...
onepix's user avatar
  • 400
0 votes
1 answer
524 views

Which mobile apps support swiping/importing private keys via QR code?

The bitcoin.org site that provides a list of wallet clients doesn't clearly show which allow for importing bitcoin via a QR paper wallet. Does anyone know a location to see which support such features,...
gesell's user avatar
  • 665
0 votes
0 answers
47 views

If I scanned my QR Code once with my android phone from a paper wallet, but now it wont..Why

I can no longer scan QR code from my paper wallet that I purchased from kiosk atm machine. I was able to scan it once, now the paper wallet has smears, rubbed off sections, etc. The kiosk machine's ...
Jenniffer Baskin's user avatar