****Update and warning: this article previously described the process of using the paper wallet service of walletgenerator{dot}net, which we used as an example because its software was able to generate keys for multiple cryptocurrencies. However, due to a recently discovered vulnerability in the software code (please read this blog post about the issue), we have decided to change the article to describe the process for creating a paper wallet from bitaddress.org. Bitaddress only generates paper wallets for Bitcoin (BTC) addresses.

At the time of writing this updated version, the Bitaddress paper wallet software is still considered safe. However, it is your own responsibility to investigate if the software has been compromised or not. The safety of using paper wallet generator software, such as Bitaddress, is not entirely without controversy, which this page further explains. We cannot guarantee the safety of any type of wallet software, so using them is entirely at your own risk.

Because paper wallets come with their own set of specific risks, for beginners, it is more recommended to use hardware wallets (such as Ledger Nano S and Trezor) for cold storage.

If you have been generating and using paper wallets from Walletgenerator{dot}net, you are advised to move all your funds out of those paper wallets into more secure alternatives asap.*****

So you want to store your crypto without having to buy a Ledger.  Or you’re worried about being hacked so you steer clear of mobile and online solutions. What is an affordable, low-tech and secure way to stash your coin? Enter the paper wallet — an old school way to safely HODL your coins without a lot of hassle.

How do paper wallets work?

Believe it or not, paper wallets, also known as cold storage, are often considered one of the more secure ways to store your cryptocurrency. We use the term “store” but in fact, your coins never leave the blockchain. Paper wallets do not store funds like regular fiat wallets. Instead, a crypto wallet securely holds the combination of your public and private keys, which gives you access to your funds on the blockchain and enables you to send and receive those funds. A more appropriate term would therefore be a “key chain” instead of “wallet”.

With a paper wallet, you print out your public and private key combination in text and often also QR format. If generated and printed in a secure fashion, this cannot be accessed by hackers or third parties as they are not stored on an online connected device. Simply scan your QR code later when it is time to ‘sweep’ your funds ready for use.

How do you generate the keys for your wallet? There are programs available that will randomly generate a public and private key for your wallet, completely offline. After creating your keys, the program will not remember/store your details (it is therefore your own responsibility to securely store your keys offline after having generated them).

Why use a paper wallet?

Similar to a savings deposit account for fiat, a paper wallet is generally used for long-term storage of your cryptocurrency — coins you’re HODLing or don’t plan to access frequently. For coins you intend to spend in the short term or to trade with, you may want to stick with a “hot” wallet — one that is connected to the internet. A cold, or paper wallet, keeps your private keys completely offline, therefore, it will not be subject to malware or hackers and you won’t have trouble accessing your funds if any of your hardware devices break.

One of the most popular sites for software to generate a paper wallet with, is Bitaddress.org. If you visit their site, please double check that you are at the correct domain.

How to create a paper wallet

Below are step-by-step instructions on how to create a paper wallet.

Most important: With any new software or process that you are going to use to handle cryptocurrency, go through the whole process of installing and transacting by sending AND receiving a tiny test amount first. Make sure that you understand the whole process and establish that it functions properly BEFORE you transact with larger amounts! Be absolutely sure that you know what you are doing in every step!

The first step is to make sure your operating software is updated and run your malware & virus protection software to make sure your device is clean. Ideally, use a brand-new PC.

Next, visit Bitaddress.org. You will find a secure link to GitHub and from there you can download the ZIP file for the wallet generator. Do not download this file from anywhere else besides directly from Bitaddress.org or its associated Github page.

Additional safety: store the software on a clean device that has never touched the internet before and that you will never connect to the internet. You can do this by saving the ZIP file on an internet connected computer to a USB stick. Plug the USB in the dedicated offline computer and extract ALL files from the ZIP folder into a folder.

How to create Bitcoin paper wallets

• Make sure your device is disconnected from the internet (preferably never connect the device to the internet)
• Open the bitaddress local file
• Open the ‘index’ file and chose the browser you want to use
• The browser opens the same page as you would see online
• Move your mouse randomly until the page shows “100%” and calculates a wallet key pair
• Carefully read and follow the instructions below the shown wallet key pair
• Now click the “Paper Wallet” link
  • DO NOT use the “brain wallet” feature; it is recognized as a NOT secure method. Only use the other featured wallet types if you expressly know what you are doing.
• Optionally, you can choose to show or hide the wallet art. Without wallet art you can fit more addresses per page.
• Select “BIP38 Encrypt” to add an extra passphrase to encrypt the private keys (read instructions below*). Enter a strong passphrase and write it down separately.
• If needed, you can change the number of wallets to generate in one go that are encrypted by the same passphrase.
• It is recommended to not change the pre-filled number of wallets per page (3 with art, 7 without art) to keep the printed wallets readable.
• Click the “generate” button and wait a few seconds for the keys to be generated.
• You will get your wallet key pairs on screen, showing the public Bitcoin address (this is what you share with others to receive Bitcoin from them) and the (encrypted) private key (NOT to be shared with ANYONE, keep this SECRET)
• Before sending any funds to your newly generated address(es), make sure you have made a backup by writing or printing the key pairs. Once you reload the page or close it, your keys are lost forever and any funds you have sent can never be recovered!
• For printing, do not use a wireless connection to the printer, but a direct connection using a cable instead. Keep in mind that a lot of printers store printed files on their own memory, which could be a vulnerability for your private keys to be compromised.
  • Therefore, a printer that does not have its own internal memory or one that hasn’t been connected to the internet before is preferred.
• After you have connected to a printer securely, press the “print” button and print the document with the key pairs. DO NOT store a digital file version!
• Print your paper wallet on high-quality paper. It is best to make a few copies and laminate them (or put in zip-lock bags) and keep in several secure places, such as a bank deposit box (note that this does introduce an alternative third party risk).
• NEVER store the details on your computer or change the format to PDF as this leaves a trace on your device – print the paper wallet info as is.
• Now you can share your public Bitcoin address for others to send Bitcoin to you.
• NEVER give anyone your *private key*! It is very important to learn the difference.

*: instructions regarding the passphrase: use a STRONG passphrase as extra security layer for your private keys. Make sure you have written the passphrase down and store it separate from your private keys. Whenever you import your private key into wallet software, you will be asked to enter the passphrase to decrypt the private key. If you have lost the passphrase, you can consider the funds in those addresses as lost. The advantage is that if your private keys are found or stolen, they are still un-spendable by the thief/hacker without the passphrase.

As with any address, it is good practice to send a small amount first, then check the blockchain before sending the rest. You will be able to use a blockchain explorer to check your balance in the usual way and send funds as you like to the PUBLIC wallet address you have just created to test it out.

How to send or spend Bitcoin from a paper wallet? “Sweep” your paper wallet.

So, you put some funds in a paper wallet.  Now it’s two years later and you have decided to buy a new car or go on a luxury holiday. How do you spend the funds being held offline in this way?

We use the term “sweep” when referring to the process of accessing funds from your paper wallet. Please keep in mind that it’s important to sweep the ENTIRE balance of any individual paper wallet address. This means that you should completely empty your paper wallet every time and send the whole balance to a new address that you control. Do not reuse a paper wallet address after sweeping/spending it. DO NOT try to spend funds directly from your paper wallet. You may want to create several smaller value paper wallets for long-term storage in the first place so that you don’t have to move your whole balance several times.

To spend your paper wallet balance, you will need to download a software wallet. Most wallets will have a “sweep wallet” feature that allows you to enter the private key manually or scan the QR code. Make sure you sweep the entire paper wallet balance as explained before. If encrypted with a passphrase, you will be asked to enter it.

After that, you need to wait until the paper wallet balance is transferred to the software wallet by a confirmed transaction on the blockchain. After confirmation, you can proceed with a transaction by using the wallet software to spend the Bitcoin as you would normally with a software wallet.

If you do not wish to keep the remaining Bitcoin on the software wallet, you will need to transfer the remaining amount from the software wallet to a NEW (unused) paper wallet address.

Keep in mind that each transaction – sweeping to your software wallet, spending from your software wallet and sending from software wallet to new paper wallet – requires an on-chain transaction and therefore, each time, a transaction fee for the network needs to be paid.

Practice the process from A to Z

As mentioned before, it is vital to practice the whole process with a tiny amount, therefore:

• After installing the paper wallet generator, generate a couple of (passphrase protected) paper wallet addresses.
• Send a tiny amount to 1 paper wallet address (make sure the amount is enough to pay for the transaction fees)
• Sweep the paper wallet with a software wallet
• Spend the amount with the software wallet
• After you get comfortable with the process, you can start moving larger amounts to your paper wallets.

Final thoughts

Using a paper wallet is different from other types of crypto wallets, but after going through the process, you will get the hang of it. Paper wallets, if generated by using a secure method, are a reasonably safe and relatively cheap way to store your crypto so they are definitely worth trying out.

Alternatively to paper wallets, another widely recommended method of cold storage is storing the seed phrase from a software wallet that is installed on an “air gapped” device (a computer that is not connected to the internet). This method improves on several vulnerabilities associated with “traditional” paper wallets. For more information on that process, you can visit this Github page.

Disclaimer:

This article was written to the best of our knowledge with the information available to us. We do not guarantee that every bit of information is completely accurate or up-to-date. Please use this information as a complement to your own research. Nothing we write in any of our articles is intended as investment advice nor as an endorsement to buy/sell/hold anything. Cryptocurrency investments are inherently risky so you should never invest more than you can afford to lose.

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