8 votes
Accepted

How Can I Ensure Private Key is Valid on my Paper Wallet?

Checking the validity of a private key is a really compute-intensive task to do by yourself, but you can do this without actually using the private key to send coins (so no need to do it using pen and ...
Gábor Héja's user avatar
6 votes

Is holding funds in a Bitcoin paper wallet safe?

Yes. A paper wallet is basically nothing more than your private key on a piece of paper. For usability it is often represented as a QR code though. You can make copies of it, and store several of ...
Erik Goff's user avatar
6 votes
Accepted

How to claim Bitcoin Cash & Bitcoin Gold from paper wallet

Go to Blockchain.info Sign up and after logging in, go to settings. Then in settings, you will see addresses as shown below: Then click on Import Bitcoin Address as shown: Then add your private key ...
remedcu's user avatar
  • 1,093
6 votes
Accepted

Handwritten paperwallet or hardwarewallet to store Bitcoins?

True. There is a standard algorithm for generating the keys from the seed words (BIP 39 / BIP 32). Most hardware wallets follow this algorithm (check before you buy). So even if the hardware device ...
Nate Eldredge's user avatar
5 votes
Accepted

Is it possible to buy bitcoins via an exchange directly into cold storage?

You can generate a wallet for cold storage offline easily. You can then ask the exchange to use a public address of that cold storage as the recipient for a transaction. You'd still pay the fee the ...
BlackBeltBob's user avatar
5 votes

What did I do wrong that caused me to lose bitcoin?

1) If you generate your paper wallet on your computer, you have to fully trust your computer 2) If you use a website for generating your paper wallet, a) you need to trust that website (hopefully its ...
Jonas Schnelli's user avatar
4 votes

I have more than 20 paper wallets with very little bitcoin in them. How can I combine all of them together?

You should import all the private keys and not sweep them. Wallets like blockchain.info has this function where it will import the private key. In that case the private key will become part of the new ...
dark knight's user avatar
  • 2,017
4 votes
Accepted

API to send bitcoins from paper/cold wallet?

You can just do it yourself instead of having to send a 3rd party your private keys. Here's one that I wrote using nodejs and bitcore-lib that takes a WIF and sends all funds to a different address. ...
m1xolyd1an's user avatar
  • 5,636
4 votes
Accepted

Is it true that sending from an address exposes the public key of a bitcoin address?

This is mostly not correct. First of all, the address is a hash of the public key only. Also, if one has a private key, the corresponding public key can be computed directly. So the most ...
Nate Eldredge's user avatar
4 votes

Where is data stored in paper wallet?

Is there global database of all wallet addresses and transactions? Yes, it is called the blockchain. You can browse it through various websites, called block explorers: e.g. http://blockchain.info, ...
Nate Eldredge's user avatar
4 votes
Accepted

I just compiled bitcoind and run for the first time. Do I already have a private key?

Bitcoin Core will automatically create a new wallet on first start. This wallet will contain 2000 private keys (unless otherwise specified by the -keypool=<n> option) and the seed used to ...
Ava Chow's user avatar
  • 70.4k
4 votes
Accepted

What does a Bitcoin lightning private key look like?

Elliptic curve private keys are just scalar integer values between 1 and n (The order of G). These can be encoded by any means, but usually they are just represented as 256-bit integers with whatever ...
Mark H's user avatar
  • 3,334
4 votes

Recovery from theft — Tracing money to exchanges

In brief: You are not going to get your money back If you try, you will lose more money The money has by now probably passed through many exchanges and mixers in many corrupt foreign countries. And ...
RedGrittyBrick's user avatar
4 votes
Accepted

BIP39 English Word List

Is there a standard in BIP39? BIP39 says: An ideal wordlist has the following characteristics: a) smart selection of words the wordlist is created in such a way that it's enough to type the first ...
RedGrittyBrick's user avatar
3 votes

What would be a safe way to store large amounts of Bitcoin long term to ensure safety from loss?

NO. Using an online source to generate private keys is incredibly unsafe for a variety of reasons. The best way would be to produce the private keys offline either with a Hardware Wallet or private ...
rny's user avatar
  • 2,418
3 votes

I have more than 20 paper wallets with very little bitcoin in them. How can I combine all of them together?

You need to Import the keys into a wallet. Send the imported bitcoin to a new address. Here is a way to do it with Bitcoin Core: Make sure the Blockchain is downloaded and fully synced (can take ...
Adam Millerchip's user avatar
3 votes
Accepted

Is there any paper wallet printing tools which can print many QR codes?

If you use bitaddress.org, click on paper wallets, you can hide art and generate and print 7 per page on standard paper or 3 per page with art - up to the amount you need. You would then need to xfer ...
user54258's user avatar
3 votes

Can I recover my bitcoins from an Armory paper wallet even if Armory ceases to function?

Short answer, you need Armory to open an Armory paper wallet. I use Armory and it does not fill me with confidence. I set one up and it was taking forever to sync with the blockchain. I think it ...
Wayland Š's user avatar
3 votes

bitcoin paper wallet--multiple addresses

The bitcoin's wallet is made up of two keys, a public key and a private one. The general title of the wallet, where you can receive money from others, is exactly the opposite: it allows you to send ...
TradingPeek's user avatar
3 votes
Accepted

bitaddress.org: is the public key the same as the Bitcoin address?

No, they're not the same thing. Paper wallets are not generated differently as/in to comparison to normal wallets. a bitcoin adress is part of a public key. The address is at its most basic just a ...
Rutger Versteegden's user avatar
3 votes

What did I do wrong that caused me to lose bitcoin?

The site bitcoinpaperwallet.com was sold in April 2018 https://github.com/cantonbecker/bitcoinpaperwallet And after this time many people wrote that their bitcoins were stolen: 1) https://www.reddit....
Perlover's user avatar
3 votes

bitaddress.org paper wallet vs. single wallet

bitaddress.org does not use the same private keys for paper wallet generation as for the single wallet. It uses the same initial entropy that you provide, but new private keys are generated for the ...
Ava Chow's user avatar
  • 70.4k
3 votes
Accepted

Prove that xpub matches xprv?

No that is not possible as it will require reverse engineering the HMAC-SHA512 function or finding a double collision that will generate the same keys. The xpub key is an encoded form of the extended ...
Ugam Kamat's user avatar
  • 7,408
3 votes

Paper wallet safety

There is a difference between a traditional paperwallet and a BIP32/39 based mnemonic and seed system. Traditionally, a paper wallet would be for a single address, with a single private key. When ...
Raghav Sood's user avatar
3 votes
Accepted

Are all 'metal wallets' functionally equivalent?

Just to be clear/nitpick, the products you've linked to are designed to act as highly resilient physical backups for a bitcoin wallet. It doesn't really make much sense to refer to these metal plates/...
chytrik's user avatar
  • 18.3k
3 votes

Long-term present in a form of cryptocurrency for newborn

I would get a wallet to generate a BIP-39 seed phrase, stamp the seed phrase onto durable metal, send money to the wallet and destroy the wallet, deleting all data.
RedGrittyBrick's user avatar
3 votes

Private key from paper wallet does not match to public key, so I can not withdraw the BTC on the paperwallet anymore

Yes, walletgenerator•net appears to be a scam website that has been around for years. According to some people on /r/bitcoin, the JavaScript code on the page contains some 60 hard coded addresses, and ...
Murch's user avatar
  • 75.3k
2 votes

I spilled a little bit of candle wax on my Bitcoin private key and now it won't scan electronically what can I do?

You can make a manual copy of the QR code. Get out a sheet of graph paper, a #2 pencil, and start copying the grid from the QR code. Count the number of rows, and make sure your graph paper is large ...
Nick ODell's user avatar
  • 29.4k
2 votes

BIP38 or Brain wallet?

BIP38 allows you to hide your private key in plain sight. Nobody knows what the private key is until they decrypt it with the password. A brainwallet is essentially generating a private key by ...
John C.'s user avatar
  • 79
2 votes

How do you sweep a paper wallet with Bitcoin-Qt?

Unlock your wallet Run Import Command in Debug Window Sweep to another key https://en.bitcoin.it/wiki/Help:How_to_import_private_keys_in_Bitcoin_Core_0.7%2B Tools needed: camera in your PC + qr code ...
Sebastian Xawery Wiśniowiecki's user avatar

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