<p>You can use also use the standard bitcoin URI QR codes to transfer bitcoin addresses from one application to another. For instance you can show your Instawallet.com bitcoin address as a QR code and drag it into the MultiBit send bitcoin screen. (www.multibit.org). It automatically parses it and creates an 'address book' entry with the bitcoin address and label 'Instawallet'.</p>

<p>Similarly, you can generate a bitcoin QR code with a bitcoin address and your name as a label in the MultiBit receive bitcoin screen, copy it and print it on the back of your business card. </p>

CC BY-SA 3.0
2011-09-07T19:46:09.640Z
2011-09-07T19:46:09.640Z
user204
<p>You can use QR codes with Shamir's Secret Sharing for making secure backups of deterministic wallets: <a href="http://code.google.com/p/bccapi/wiki/ManagingLongPassphrases" rel="nofollow">http://code.google.com/p/bccapi/wiki/ManagingLongPassphrases</a></p>

CC BY-SA 3.0
2014-02-06T16:20:29.200Z
Speaking of which, here's a pretty straightforward, easy-to-read python implementation of Shamir's Secret Sharing: https://github.com/halfmoonlabs/secretsharing
Ryan Shea
CC BY-SA 3.0
2014-02-06T19:51:37.973Z
We just need to define a standard for it
Jan
CC BY-SA 3.0
2011-09-07T20:52:43.487Z
2011-09-07T20:52:43.487Z
Jan
<p>There was a thread on <a href="https://bitcointalk.org/index.php?topic=2038.0" rel="nofollow">bitcointalk</a> about creating a specification to encode additional data (besides the address) in QR codes. This would work with a key/value pair and it could be used for a lot of things. Here is an example for merchant/buyer interaction:</p>

<blockquote>
  <p><strong>Merchant request for direct payment via bitcoin network.</strong></p>
  
  <p>Code:</p>
  
  <p><code>btcpayment-request1: name=“My Bitcoin Inc.”; pubkey=1LGpwDU5djqsR1X14Tcass3y9fULTzxJq3; amount=300</code></p>
  
  <p>Using this QR-code, the mobile phone knows enough to ask the user if
  they wish to pay 300 BTC to My Bitcoin, Inc. at the given bitcoin
  address.  Presumably the mobile phone has the ability to make bitcoin
  payments, either directly (a lightweight bitcoin client) or indirectly
  via a payment API such as this.</p>
</blockquote>

CC BY-SA 3.0
2011-09-04T13:54:13.727Z
2011-09-04T13:54:13.727Z
nmat
<p>I believe QR will be to BTC what paper is to cash. I even registered long ago QRBitCoins.com (and others) and am now waiting for the right project to prompt some work. I thought I should tell people in case there is any interesting on-going project that would need a good QR domain.</p>

CC BY-SA 3.0
2011-12-05T09:32:03.287Z
+1 for an interesting insight into the relationship between Bitcoin and QR codes
Gary
CC BY-SA 3.0
2011-12-04T21:24:27.440Z
2011-12-05T09:33:31.353Z
2011-12-05T09:33:31.353Z
Narydu
<p>If I recall correctly, a bitcoin transaction can be coded to require a password to access them. Therefore, you could make the QR codes a way to hold a bitcoin outside of a wallet.</p>

CC BY-SA 3.0
2011-09-09T06:22:09.690Z
+1 for an interesting script use case. Details of the shared secret approach are referenced here: http://bitcoin.stackexchange.com/questions/547/useful-alternative-bitcoin-transaction-scripts
Gary
CC BY-SA 3.0
2011-09-09T03:31:57.567Z
2011-09-09T03:31:57.567Z
Erock
<p><strong>Inexpensive 2-factor authentication</strong></p>

<p>A QR code could be used a contributor to a 2-factor authentication ("Something I have and something I know") system. When making payments a person could input a PIN as one part, and scan a QR code they carry with them in their physical wallet (could be printed on a plastic card for example) as the second part. </p>

<p>This approach could be used as a pre-authentication to provide the wallet application with temporary access to a private key held on the mobile device. This private key could then unlock the local wallet or act as an authentication key to a remove service. </p>

<p>It does have weaknesses though:</p>

<ul>
<li><p>A high-definition CCTV mounted near the point of sale could catch people whipping out their plastic card in preparation and a bit of image manipulation would harvest QR codes</p></li>
<li><p>It's a bit fiddly and is probably only for the security conscious</p></li>
</ul>

<p>Food for thought.</p>

CC BY-SA 3.0
2011-09-06T06:02:59.640Z
2011-09-06T06:02:59.640Z
Gary
<p>In terms of marketing, here is a very nice QR code that could be used for spreading the word about Bitcoin. It contains a link to <a href="http://www.bitcoin.org" rel="nofollow noreferrer">bitcoin.org</a>. See <a href="https://bitcointalk.org/index.php?topic=30981.0" rel="nofollow noreferrer">this thread</a> on bitcointalk.org for more information. It was created by phelix at <a href="http://bitcoinx.com/" rel="nofollow noreferrer">bitcoinx.com</a>.</p>

<p><img src="https://i.sstatic.net/nm9rw.png" alt="Bitcoin Extreme QR code"></p>

CC BY-SA 4.0
2011-09-04T11:21:38.030Z
2018-12-30T23:11:25.417Z
2018-12-30T23:11:25.417Z
D.H.
<p>Anyone who has recently used one of the Bitcoin wallets on a mobile device (and some <a href="http://multibit.org">desktop  clients</a>) will have seen a Bitcoin <a href="http://en.wikipedia.org/wiki/QR_code">QR code</a>. Clearly, QR codes allow for a succinct method for transferring complex information in a reliable and error-resistant manner.</p>

<p>Naturally, the most obvious use of a QR code is for encoding a payment request URI. However, are there any other benefits that QR codes can bring to Bitcoin beyond this? </p>

<p>I'm thinking in terms of marketing, exotic transaction types that sort of thing.</p>

<qrcode>
What additional benefits can QR codes bring to Bitcoin applications beyond payment requests?
Gary
# What additional benefits can QR codes bring to Bitcoin applications beyond payment requests?

(Asked by: username_0 on 2011-09-04)

Anyone who has recently used one of the Bitcoin wallets on a mobile device (and some [desktop clients](http://multibit.org)) will have seen a Bitcoin [QR code](http://en.wikipedia.org/wiki/QR_code). Clearly, QR codes allow for a succinct method for transferring complex information in a reliable and error-resistant manner.

Naturally, the most obvious use of a QR code is for encoding a payment request URI. However, are there any other benefits that QR codes can bring to Bitcoin beyond this?

I'm thinking in terms of marketing, exotic transaction types that sort of thing.

**Tags:** qrcode


---

## 7 answers

### Answer by username_7 on 2011-09-04. Score: 7 | Accepted answer

In terms of marketing, here is a very nice QR code that could be used for spreading the word about Bitcoin. It contains a link to [bitcoin.org](http://www.bitcoin.org). See [this thread](https://bitcointalk.org/index.php?topic=30981.0) on bitcointalk.org for more information. It was created by phelix at [bitcoinx.com](http://bitcoinx.com/).

![Bitcoin Extreme QR code](https://i.sstatic.net/nm9rw.png)


---

### Answer by username_1 on 2011-09-07. Score: 3

You can use also use the standard bitcoin URI QR codes to transfer bitcoin addresses from one application to another. For instance you can show your Instawallet.com bitcoin address as a QR code and drag it into the MultiBit send bitcoin screen. (www.multibit.org). It automatically parses it and creates an 'address book' entry with the bitcoin address and label 'Instawallet'.

Similarly, you can generate a bitcoin QR code with a bitcoin address and your name as a label in the MultiBit receive bitcoin screen, copy it and print it on the back of your business card.


---

### Answer by username_2 on 2011-09-07. Score: 3

You can use QR codes with Shamir's Secret Sharing for making secure backups of deterministic wallets: <http://code.google.com/p/bccapi/wiki/ManagingLongPassphrases>

> **Comments:**
> **username_3**: Speaking of which, here's a pretty straightforward, easy-to-read python implementation of Shamir's Secret Sharing: https://github.com/halfmoonlabs/secretsharing  
> **username_2**: We just need to define a standard for it  

---

### Answer by username_4 on 2011-09-04. Score: 1

There was a thread on [bitcointalk](https://bitcointalk.org/index.php?topic=2038.0) about creating a specification to encode additional data (besides the address) in QR codes. This would work with a key/value pair and it could be used for a lot of things. Here is an example for merchant/buyer interaction:

> **Merchant request for direct payment via bitcoin network.**
>
> Code:
>
> `btcpayment-request1: name=“My Bitcoin Inc.”; pubkey=1LGpwDU5djqsR1X14Tcass3y9fULTzxJq3; amount=300`
>
> Using this QR-code, the mobile phone knows enough to ask the user if
> they wish to pay 300 BTC to My Bitcoin, Inc. at the given bitcoin
> address. Presumably the mobile phone has the ability to make bitcoin
> payments, either directly (a lightweight bitcoin client) or indirectly
> via a payment API such as this.


---

### Answer by username_5 on 2011-12-04. Score: 1

I believe QR will be to BTC what paper is to cash. I even registered long ago QRBitCoins.com (and others) and am now waiting for the right project to prompt some work. I thought I should tell people in case there is any interesting on-going project that would need a good QR domain.

> **Comments:**
> **username_0**: +1 for an interesting insight into the relationship between Bitcoin and QR codes  

---

### Answer by username_6 on 2011-09-09. Score: 1

If I recall correctly, a bitcoin transaction can be coded to require a password to access them. Therefore, you could make the QR codes a way to hold a bitcoin outside of a wallet.

> **Comments:**
> **username_0**: +1 for an interesting script use case. Details of the shared secret approach are referenced here: http://bitcoin.stackexchange.com/questions/547/useful-alternative-bitcoin-transaction-scripts  

---

### Answer by username_0 on 2011-09-06. Score: 0

**Inexpensive 2-factor authentication**

A QR code could be used a contributor to a 2-factor authentication ("Something I have and something I know") system. When making payments a person could input a PIN as one part, and scan a QR code they carry with them in their physical wallet (could be printed on a plastic card for example) as the second part.

This approach could be used as a pre-authentication to provide the wallet application with temporary access to a private key held on the mobile device. This private key could then unlock the local wallet or act as an authentication key to a remove service.

It does have weaknesses though:

* A high-definition CCTV mounted near the point of sale could catch people whipping out their plastic card in preparation and a bit of image manipulation would harvest QR codes
* It's a bit fiddly and is probably only for the security conscious

Food for thought.


---

