The Card Wallet is a co-production of Coinfinity and the Austrian State Printing House, and offers a simple way to securely store Bitcoin offline in form of a tamper-proof card. The Card Wallet is manufactured in the high-security room of the Austrian State Printing House in an isolated offline system, using Coinfinity's Secure Entropy Technology. The private key is sealed tamper-proof before the card leaves the production machine, and immediately deleted after the process so that not even the staff at the high-security room can ever see the key. High-quality security materials and tamper-proof features prevent a manipulation of the card.
Frequently Asked Questions
What is the Card Wallet?
Where can I buy the Card Wallet?
The Card Wallet is up for sale in our webshop. The Card Wallet is also available in our front office in Graz.
How much does the Card Wallet cost?
The price is 39.90 Euro, VAT included.
How is the Card Wallet delivered?
The Card Wallet is directly sent by our shipping partner Copiaro
Which personal data is stored during a purchase?
How long is personal data stored?
As soon as an order is older than 90 days, we actively delete all personal data from the web store, even without a request from the customer.
In which cases can I use the Card Wallet?
The Card Wallet is an ideal solution for secure long-term offline storage of Bitcoin. Its characteristics make Bitcoin easy to give, transfer, or inherit, as the Card Wallet transforms them into a physical good. The Card Wallet is ideal for those who have not had any experience handling cryptocurrencies so far.
I'm a Bitcoin expert, can't I just generate private keys myself?
Not relying on a third party to generate private keys always is the best option – assuming you have the technical expertise. If you know what needs to be done to generate private keys in a secure way, and also know how to create a long-term storage, then doing this all on your own would be the best option. For all other users, especially Bitcoin novices, the Card Wallet is a good alternative, as it does not require any technical expertise on the user-side.
Is the Card Wallet suitable for short-term storage of Bitcoin?
The Card Wallet’s purpose is to keep Bitcoin safe for long periods of time. The Card Wallet is not suitable for short-term storage or regular sending of Bitcoin. Hardware wallets are a good alternative in this case.
Can I use the Card Wallet for transactions, similar to a debit or credit card?
No, the Card Wallet is not a credit or debit card and can not be used at POS terminals. It neither contains a chip nor a magnetic stripe.
How can I transfer or sell Bitcoin stored on the Card Wallet?
Uncover the private key and import it into a digital wallet to access your Bitcoin. Once you have imported the private key, you can transfer your Bitcoin to other addresses or an exchange account. Always make sure to secure your private key from others’ views. If you need assistance, you can personally come to our office in Graz with your Card Wallet at any time, so that we can guide you through this process. For an appointment, please contact us first.
Is the Card Wallet also available for other cryptocurrencies?
The Card Wallet currently is available for Bitcoin and Ethereum, as well as for all tokens on the Ethereum blockchain.
In what way does the Card Wallet differ from Hardware Wallets?
Hardware Wallets are certainly a good alternative and preferred in terms of security compared to online wallets or smartphone wallets. Long-term safekeeping of Bitcoin with hardware wallets is possible, but these points should be considered:
- The secure installation of a hardware wallet requires a certain technical knowledge.
- Hardware Wallets need to be updated regularly.
- The necessary interfaces (for example USB) may no longer be available in the future.
- Hardware wallets are not immune to attacks; see https://wallet.fail/ for further information.
The Card Wallet reduces Bitcoin to the essentials - the private key - which is stored completely without hardware dependencies, and is easy to read out, even in decades.
Can't I just create a paper wallet myself?
If you have the technical expertise to create a paper wallet in a safe way, then that's certainly a good option for you. For the vast majority of people, this is anything but easy. Apart from the time and necessary technical requirements, there are a number of potential sources of error and critical points that should be considered:
- Which software do you use for the generation? Who created it, and was it audited?
- On which device do you run the software, and how safe is this device?
- Can you ensure that the private keys are not transferred to the internet during the generation?
- How was the necessary entropy generated, and is it big enough?
- On which medium do you print the private key, and how durable is it?
- Can you make sure your printer does not save a copy of the private key?
- Can you ensure that no one else had access to the private key during generation, printing, and beyond?
- Do you have a way to seal the private key tamper-proof?
The Card Wallet is an ideal alternative for those who do not want to worry about these things.
What is a private key?
The private key serves as a proof of ownership to the Bitcoin network. The private key signs transactions which then are validated by the Bitcoin network. Without the possession of the private key, access is not possible.
What is the private key made of?
The private key is a random 256-bit number. This is long set of numbers, and the random selection ensures that the same private key is not generated twice. But it is very important that the random number generator actually generates random numbers and not just pseudo-random numbers. We ensure this by using our Secure Entropy Technology (SET).
What is Secure Entropy Technology (SET)?
To generate the private keys, several independent random number generators are used. The SET defines how multiple entropy sources can be mixed to generate the random number and validates at the same time that all entropy sources have actually been included in the generation of the random numbers. This means that even if all but one entropy source were undermined or buggy, the random numbers would still be completely secure and random. The SET prevents targeted attacks by an infiltrated random number generator, as well as any unintentional errors in the generation and processing of the random numbers. The generated card wallets are checked by random samples. Any deviation that suggests the random numbers have been manipulated leads to the complete destruction of the batch and leads to further surveys of the cause.
Is the private key saved?
The private key printed on the back of the card exists exclusively on the respective Card Wallet, there is no copy of the private key. The generated key never leaves the production machine, and can not be viewed by employees at any time. All data carriers of the machine are deleted at the end of a production process, using secure procedures.
Can the Bitcoin holdings of the Card Wallets be monitored by Coinfinity or the Austrian State Printing House?
Even the public Bitcoin address printed on the front side exists solely on the Card Wallet and is saved nowhere else. There is no way to monitor the Bitcoin holdings of the Card Wallets.
How can I check the authenticity of the Card Wallet?
All informations about the security features of the Card Wallet can be found at: How-To
Is the Austrian State Printing House in state ownership?
No, the "Österreichische Staatsdruckerei GmbH" is a privately-owned company, not a state-owned institution.
Which payment methods are available?
We accept payments via Bitcoin, eps, giropay and credit card. You can find an overview as well as further explanations on our page in the payment methods section.
How to gift a Card Wallet?
To gift the Card Wallet visit our webshop cardwallet.com/shop.