Today we will consider the meaning of the words “bitcoin private key” – what it is for, how to get it and how to store it correctly.
While the public key, or address, is a means of identifying the wallet, a kind of login, the private key is strictly confidential information. Outwardly, it looks like a set of characters, by entering which, the user gains access to account management. Private (they are also called private or private) keys are stored in a special file, public ones are formed using a cryptographic method based on private ones.
Technically, a “private key” is a 256-bit number that is randomly generated when creating a wallet account. The range is very large, so it is impossible to guess the key by the selection method, it can be any number from one to 10 to the power of 77.
- 1 What the public and private keys of a bitcoin wallet look like
- 2 How to create private bitcoin keys
- 3 How to get (export) the private key of bitcoin
- 4 How to securely store private keys
What the public and private keys of a bitcoin wallet look like
The private bitcoin key is encoded in the following formats: Base64, MINI, Hex, WIF, compressed WIF. They are all interconnected and transform one into another:
- WIF format (51 characters, “5” at the beginning): 5JPeWYZx922hXi49Lg2RJPwLfqcmDGS9YegMNgANvx8cJa6kNK8.
- Most cryptocurrency wallets use WIF-compressed format (52 characters, starting with “L” or “K”) for storing private keys: KykxZQLSNPYVtYCsoqFGFnEqpRar997zihJgvfrPo8LapFrAtaea.
- Hex format (64 characters): 4BBFF74CA25A2A00409DCB24EC0418E9A41F9B3B56216A183E0E9731F4589DC6.
- Base64 format (44 characters): S7 / 3TKJaKgBAncsk7AQY6aQfmztWIWoYPg6XMfRYncY =.
The picture shows one private bitcoin key in different formats:
Public address (key)
The appearance of a public bitcoin key in various formats:
- Most used in wallets is a short address. It has the form 1BSUkuwtdM7gkdy6W4Q954gNKWBgy4A19Q and always starts with one or three (segwit address).
Public keys (public key) are visible to everyone and are used as an address for sending or receiving bitcoins. An unlimited number of public keys can be generated in one wallet. Each will have its own private key.
In simple words, any cryptocurrency wallet is a private key from which a public key is generated.
How to create private bitcoin keys
When creating any Bitcoin wallet, a private key is created. Depending on the type of wallet, you can have control over them or not. The latter case is more related to online services where you can go through a simple registration, get a bitcoin address, but private keys are not available. The owners of these online wallets have control over them. Therefore, we recommend choosing crypto wallets with the ability to upload private keys or save the seed.
- Local. Installed on desktop or mobile devices. These include Jaxx, Electrum, Coinomi, Exodus and others. They are divided into “thin” and “thick”, depending on the way of accessing the blockchain network.
- Online wallets. To create them, you usually need to provide an email and password. Such services may or may not provide the ability to view private keys. Popular sites for storing crypto coins: blockchain.com.
- Cryptocurrency exchanges. After creating an account, wallets for cryptocurrencies are available, which are in the site’s listing. Private keys are not provided. You can make a deposit to the provided address, trade cryptocurrency and make a withdrawal. Popular trading platforms: LocalBitcoins, EXMO, Binance, Huobi, BitMEX and others.
- Hardware wallets. The safest option is to keep cryptoassets safe. The owner has full control over all private keys, and their theft is impossible. Produced by hardware devices Ledger, Trezor and others.
- Paper ones. It can be just a written down private key on paper or services that generate it and provide the ability to print and save. The method relates to the “cold” storage of cryptocurrencies.
How to get (export) the private key of bitcoin
There are situations when you need to get your private key from the wallet for one purpose or another. Let’s see how to do this.
Extraction (export) of private keys from crypto wallets
The Exodus “thin” desktop wallet is used as an example. In it, you need to perform the export operation of the private bitcoin key. Initially, it is reliably hidden, since the developers rightly believe that it is better for an inexperienced user not to try to produce it. Wrong actions are fraught with the loss of funds from the wallet.
- Activate the “Developer Menu”. On Windows and Linux, this action is performed by pressing the keyboard shortcut Ctrl + Shift + D.
- Select the cryptocurrency whose private key you are interested in at the moment. Go through the points: “Developer” – “Assets” – “Bitcoin” or another selected currency – “Export Private Keys”.
- In the window that appears, confirm your desire by pressing the “I’m sure” button.
- A folder named “Exodus-export” will appear on the desktop, inside – a CSV file. Copy this file to a safe place, delete the folder immediately.
You can open the file through the text editor Libre Office, Wordpad, Exel, standard Notepad, etc. The “PRIVKEY” column will contain an alphanumeric combination – this is the private (private) bitcoin key:
Obtaining a private key from an online Blockchain wallet
Let’s take a look at how to get a private key in the popular Blockchain online wallet. There is no key export function in the settings. You need to use the seed-phrase, which is located at “Settings” – “Security” – “Phrase for wallet recovery”. Copy all words and go to iancoleman.io generator. Specify the number of words (12) and insert them into the “BIP39 Mnemonic” form.
Scroll down the page to the “Derived Addresses” section. It will contain the address, public and private keys.
Obtaining a key in a paper wallet
Paper wallets generate private keys locally by executing a script in the browser.
After collecting random entropy, the compressed bitcoin address and private key in compressed WIF format will be displayed. What to do with them is clear from the picture:
Service for creating paper wallets: bitaddress.org.
What is a deterministic wallet (HD wallet), seed phrase
In 2011, to solve a number of problems with anonymity, Bitcoin Core developers released HD Wallet. HD stands for “hierarchical deterministic”, that is, “hierarchically deterministic”. It sounds incomprehensible, but in fact everything is not so difficult.
In the context of cryptocurrencies, the word “hierarchy” refers to the relationship between elements. In this case, it becomes possible to use one address to find out the second, and also to use a secret seed phrase to generate many related addresses at once.
An example of a seed (backup phase) in a Blockchain wallet (12 words in total):
A “deterministic” system is one where no chances are allowed in the process of forming future states. That is, specific inputs will always produce a specific result.
Advantages of HD wallet technology:
- Strengthening anonymity. The owner of the HD wallet has one copy of the software wallet with one secret key (also called the “seed” or “master key”). When combining a seed with hash functions, an infinite number of related addresses are formed. The connection is invisible from the outside. These addresses are called “child” addresses.
- Ease of memorizing the seed phrase. Writing or learning a 12-word code is much easier than storing private keys for each individual bitcoin address.
- Convenient backup. Many users face problems with backing up mobile wallets on iOS or Android – it becomes necessary to use the same key, and this is a direct security threat. HD wallet does not require any backups at all, it is enough to print or save the seed phrase in a safe place.
The technology is implemented in the Armory add-on for Bitcoin Core, Electrum wallets, MultiBit HD, BitGo, CarbonWallet, The Hive, Mycelium Bitcoin Wallet, Green Address, Trezor and others.
How to securely store private keys
When using internet wallets, it should be understood that the keys are stored on the servers of the developer company. The user personally owns the private key only in the case of using desktop, hardware or paper wallets.
Code storage options:
- On the paper.
- On a USB flash drive as a screenshot or photo, pdf file.
- On a hard disk, including a removable one.
- On a physical coin, a metal plate (a kind of analogue of a hardware “cold” wallet in the form of a cryptocurrency coin).
- In mind.
None of the above methods provide a 100% guarantee of the safety of the key, in each case there is a possibility of physical damage, hacking or theft. So everyone makes a choice based on their own considerations.
There are many cybercriminals on the Internet who dream of stealing the private key of bitcoin. They can seduce with free tokens, offer to get new coins, and in return they are asked to upload a private key to the network or a program they have created. In no case should this be done.