Private key - Revision history

Belcher: Add line about seed phrases to introduction

2019-05-04T14:14:24Z

Add line about seed phrases to introduction

← Older revision		Revision as of 14:14, 4 May 2019
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	Because the private key is the "ticket" that allows someone to spend bitcoins, it is important that these are kept secret and safe.		Because the private key is the "ticket" that allows someone to spend bitcoins, it is important that these are kept secret and safe.
	Private keys can be kept on computer files, but are also often [[Seed phrase\|written on paper]].		Private keys can be kept on computer files, but are also often [[Seed phrase\|written on paper]].

			Private keys themselves are almost never handled by the user, instead the user will typically be given a [[seed phrase]] that encodes the same information as private keys.

	Some wallets allow private keys to be imported without generating any transactions while other wallets or services require that the private key be swept.		Some wallets allow private keys to be imported without generating any transactions while other wallets or services require that the private key be swept.

Belcher: Add some internal links

2019-05-04T14:09:47Z

Add some internal links

← Older revision		Revision as of 14:09, 4 May 2019
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	A '''private key''' in the context of Bitcoin is a secret number that allows bitcoins to be spent.		A '''private key''' in the context of Bitcoin is a secret number that allows bitcoins to be spent.
	Every Bitcoin wallet contains one or more private keys, which are saved in the wallet file.		Every Bitcoin wallet contains one or more private keys, which are saved in the wallet file.
	The private keys are mathematically related to all Bitcoin ~~addresses~~ generated for the wallet.		The private keys are mathematically related to all Bitcoin [[address]]es generated for the wallet.

	Because the private key is the "ticket" that allows someone to spend bitcoins, it is important that these are kept ~~secure~~.		Because the private key is the "ticket" that allows someone to spend bitcoins, it is important that these are kept secret and safe.
	Private keys can be kept on computer files, but ~~in some cases~~ are also ~~short enough that they can be printed~~ on paper.		Private keys can be kept on computer files, but are also often [[Seed phrase\|written on paper]].

	Some wallets allow private keys to be imported without generating any transactions while other wallets or services require that the private key be swept.		Some wallets allow private keys to be imported without generating any transactions while other wallets or services require that the private key be swept.
	When a private key is swept, a transaction is broadcast that sends the balance controlled by the private key to a new address in the wallet.		When a private key is swept, a transaction is [[Transaction broadcasting\|broadcast]] that sends the balance controlled by the private key to a new address in the wallet.
	Just as with any other transaction, there is risk of swept transactions to be double-spending.		Just as with any other transaction, there is risk of swept transactions to be [[Irreversible Transactions\|double-spending]].

	In contrast, bitcoind provides a facility to import a private key without creating a sweep transaction.		In contrast, bitcoind provides a facility to import a private key without creating a sweep transaction.
	This is considered very dangerous, and not intended to be used even by power users or experts except in very specific cases.		This is considered very dangerous, and not intended to be used even by power users or experts except in very specific cases. Importing keys could lead to the Bitcoins being stolen at any time, from a wallet which has imported an untrusted or otherwise insecure private key - this can include private keys [[Cold storage\|generated offline and never seen by someone else]]<ref>[https://bitcoin.stackexchange.com/questions/29948/why-doc-says-importing-private-keys-is-so-dangerous Bitcoin StackExchange - Why doc says importing private keys is so dangerous?]</ref><ref>[https://bitcoin.stackexchange.com/questions/18619/why-so-many-warnings-about-importing-private-keys Bitcoin StackExchange - Why so many warnings about importing private keys?]</ref>.
	Bitcoins ~~can be easily~~ stolen at any time, from a wallet which has imported an untrusted or otherwise insecure private key - this can include private keys generated offline and never seen by someone else<ref>[https://bitcoin.stackexchange.com/questions/29948/why-doc-says-importing-private-keys-is-so-dangerous Bitcoin StackExchange - Why doc says importing private keys is so dangerous?]</ref><ref>[https://bitcoin.stackexchange.com/questions/18619/why-so-many-warnings-about-importing-private-keys Bitcoin StackExchange - Why so many warnings about importing private keys?]</ref>.

	==An example private key==		==An example private key==

Belcher: Reverted edits by Apirone.com (talk) to last revision by Belcher

2019-02-15T19:31:27Z

Reverted edits by Apirone.com (talk) to last revision by Belcher

← Older revision		Revision as of 19:31, 15 February 2019
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	==See Also==		==See Also==
	* [https://allprivatekeys.com/ Private keys directory and leaked keys database]
	* [[Paper wallet]]		* [[Paper wallet]]
	* [[How to import private keys]]		* [[How to import private keys]]

Apirone.com: /* See Also */

2019-02-11T06:07:23Z

Belcher: renamed all "mnemonic phrase" to "seed phrase"

2018-07-17T12:33:08Z

renamed all "mnemonic phrase" to "seed phrase"

← Older revision		Revision as of 12:33, 17 July 2018
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	Wallet software may use a [[BIP 0032\|BIP 32]] seed to generate many private keys and corresponding public keys from a single secret value. This is called a ''hierarchical deterministic wallet'', or ''HD wallet'' for short. The seed value, or ''master extended key'', consists of a 256-bit private key and a 256-bit ''chain code'', for 512 bits in total. The seed value should not be confused with the private keys used directly to sign Bitcoin transactions.		Wallet software may use a [[BIP 0032\|BIP 32]] seed to generate many private keys and corresponding public keys from a single secret value. This is called a ''hierarchical deterministic wallet'', or ''HD wallet'' for short. The seed value, or ''master extended key'', consists of a 256-bit private key and a 256-bit ''chain code'', for 512 bits in total. The seed value should not be confused with the private keys used directly to sign Bitcoin transactions.

	Users are strongly advised to use HD wallets, for safety reasons: An HD wallet only needs to be backed up once typically using a [[~~mnemonic~~ phrase]]; thereafter in the future, that single backup can always deterministically regenerate the same private keys. Therefore, it can safely recover all addresses, and all funds sent to those addresses. Non-HD wallets generate a new randomly-selected private key for each new address; therefore, if the wallet file is lost or damaged, the user will irretrievably lose all funds received to addresses generated after the most recent backup.		Users are strongly advised to use HD wallets, for safety reasons: An HD wallet only needs to be backed up once typically using a [[seed phrase]]; thereafter in the future, that single backup can always deterministically regenerate the same private keys. Therefore, it can safely recover all addresses, and all funds sent to those addresses. Non-HD wallets generate a new randomly-selected private key for each new address; therefore, if the wallet file is lost or damaged, the user will irretrievably lose all funds received to addresses generated after the most recent backup.

	==Base58 Wallet Import format==		==Base58 Wallet Import format==

Belcher: added to category technical

2017-12-21T18:49:16Z

added to category technical

← Older revision		Revision as of 18:49, 21 December 2017
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	[[es:Clave privada]]		[[es:Clave privada]]

			[[Category:Technical]]

Belcher: /* Hierarchical Deterministic (HD) Wallet Keys */ added mention and link to mnemonic phrases

2017-12-21T18:47:37Z

Hierarchical Deterministic (HD) Wallet Keys: added mention and link to mnemonic phrases

← Older revision		Revision as of 18:47, 21 December 2017
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	Wallet software may use a [[BIP 0032\|BIP 32]] seed to generate many private keys and corresponding public keys from a single secret value. This is called a ''hierarchical deterministic wallet'', or ''HD wallet'' for short. The seed value, or ''master extended key'', consists of a 256-bit private key and a 256-bit ''chain code'', for 512 bits in total. The seed value should not be confused with the private keys used directly to sign Bitcoin transactions.		Wallet software may use a [[BIP 0032\|BIP 32]] seed to generate many private keys and corresponding public keys from a single secret value. This is called a ''hierarchical deterministic wallet'', or ''HD wallet'' for short. The seed value, or ''master extended key'', consists of a 256-bit private key and a 256-bit ''chain code'', for 512 bits in total. The seed value should not be confused with the private keys used directly to sign Bitcoin transactions.

	Users are strongly advised to use HD wallets, for safety reasons: An HD wallet only needs to be backed up once; thereafter in the future, that single backup can always deterministically regenerate the same private keys. Therefore, it can safely recover all addresses, and all funds sent to those addresses. Non-HD wallets generate a new randomly-selected private key for each new address; therefore, if the wallet file is lost or damaged, the user will irretrievably lose all funds received to addresses generated after the most recent backup.		Users are strongly advised to use HD wallets, for safety reasons: An HD wallet only needs to be backed up once typically using a [[mnemonic phrase]]; thereafter in the future, that single backup can always deterministically regenerate the same private keys. Therefore, it can safely recover all addresses, and all funds sent to those addresses. Non-HD wallets generate a new randomly-selected private key for each new address; therefore, if the wallet file is lost or damaged, the user will irretrievably lose all funds received to addresses generated after the most recent backup.

	==Base58 Wallet Import format==		==Base58 Wallet Import format==

Nullius: Clarify, distinguish, and briefly explain the 512-bit seeds used in BIP-32 HD wallets.

2017-12-21T02:01:24Z

Clarify, distinguish, and briefly explain the 512-bit seeds used in BIP-32 HD wallets.

← Older revision		Revision as of 02:01, 21 December 2017
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	The range of valid private keys is governed by the [[secp256k1]] ECDSA standard used by Bitcoin.		The range of valid private keys is governed by the [[secp256k1]] ECDSA standard used by Bitcoin.

	~~Newer wallets~~ may use [[BIP 0032\|BIP 32]] ~~seeds~~ for ~~their~~ private keys, ~~which~~ can ~~be as long as 512 bits~~.		==Hierarchical Deterministic (HD) Wallet Keys==
			{{main\|Hierarchical deterministic wallet}}

			Wallet software may use a [[BIP 0032\|BIP 32]] seed to generate many private keys and corresponding public keys from a single secret value. This is called a ''hierarchical deterministic wallet'', or ''HD wallet'' for short. The seed value, or ''master extended key'', consists of a 256-bit private key and a 256-bit ''chain code'', for 512 bits in total. The seed value should not be confused with the private keys used directly to sign Bitcoin transactions.

			Users are strongly advised to use HD wallets, for safety reasons: An HD wallet only needs to be backed up once; thereafter in the future, that single backup can always deterministically regenerate the same private keys. Therefore, it can safely recover all addresses, and all funds sent to those addresses. Non-HD wallets generate a new randomly-selected private key for each new address; therefore, if the wallet file is lost or damaged, the user will irretrievably lose all funds received to addresses generated after the most recent backup.

	==Base58 Wallet Import format==		==Base58 Wallet Import format==

Nullius: Make quick fix to incorrect info. That section should probably be rewritten.

2017-12-21T01:05:37Z

Make quick fix to incorrect info. That section should probably be rewritten.

← Older revision		Revision as of 01:05, 21 December 2017
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	==An example private key==		==An example private key==
	In Bitcoin, a private key is ~~usually~~ a 256-bit number ~~(some newer wallets may use between 128 and 512 bits)~~, which can be represented one of several ways.		In Bitcoin, a private key is a 256-bit number, which can be represented one of several ways.
	Here is a private key in hexadecimal - 256 bits in hexadecimal is 32 bytes, or 64 characters in the range 0-9 or A-F.		Here is a private key in hexadecimal - 256 bits in hexadecimal is 32 bytes, or 64 characters in the range 0-9 or A-F.

Taras at 07:12, 10 August 2017

2017-08-10T07:12:56Z

← Older revision		Revision as of 07:12, 10 August 2017
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			{{sample}}
	A '''private key''' in the context of Bitcoin is a secret number that allows bitcoins to be spent.		A '''private key''' in the context of Bitcoin is a secret number that allows bitcoins to be spent.
	Every Bitcoin wallet contains one or more private keys, which are saved in the wallet file.		Every Bitcoin wallet contains one or more private keys, which are saved in the wallet file.
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	Here is a private key in hexadecimal - 256 bits in hexadecimal is 32 bytes, or 64 characters in the range 0-9 or A-F.		Here is a private key in hexadecimal - 256 bits in hexadecimal is 32 bytes, or 64 characters in the range 0-9 or A-F.

	~~E9 87 3D 79 C6 D8 7D C0 FB 6A 57 78 63 33 89 F4 45 32 13 30 3D A6 1F 20 BD 67 FC 23 3A A3 32 62~~		E9873D79C6D87DC0FB6A5778633389{{taggant private key}}F4453213303DA61F20BD67FC233AA33262

	==Range of valid ECDSA private keys==		==Range of valid ECDSA private keys==
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	==Base58 Wallet Import format==		==Base58 Wallet Import format==
			{{main\|Wallet import format}}
	When importing or sweeping ECDSA private keys, a shorter format known as [[wallet import format]] is often used, which offers a few advantages.		When importing or sweeping ECDSA private keys, a shorter format known as [[wallet import format]] is often used, which offers a few advantages.
	The wallet import format is shorter, and includes built-in error checking codes so that typos can be automatically detected and/or corrected (which is impossible in hex format) and type bits indicating how it is intended to be used.		The wallet import format is shorter, and includes built-in error checking codes so that typos can be automatically detected and/or corrected (which is impossible in hex format) and type bits indicating how it is intended to be used.
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	For private keys associated with uncompressed public keys, they are 51 characters and always start with the number 5 on mainnet (9 on testnet). Private keys associated with compressed public keys are 52 characters and start with a capital L or K on mainnet (c on testnet). This is the same private key in (mainnet) wallet import format:		For private keys associated with uncompressed public keys, they are 51 characters and always start with the number 5 on mainnet (9 on testnet). Private keys associated with compressed public keys are 52 characters and start with a capital L or K on mainnet (c on testnet). This is the same private key in (mainnet) wallet import format:

	~~5Kb8kLf9zgWQnogidDA76MzPL6TsZZY36hWXMssSzNydYXYB9KF~~		5Kb8kLf9zgWQnogidDA76Mz{{taggant private key}}PL6TsZZY36hWXMssSzNydYXYB9KF

	When a WIF private key is imported, it always corresponds to exactly one [[Address\|Bitcoin address]].		When a WIF private key is imported, it always corresponds to exactly one [[Address\|Bitcoin address]].
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	The mathematical conversion is somewhat complex and best left to a computer, but it's notable that the WIF guarantees it will always correspond to the same address no matter which program is used to convert it.		The mathematical conversion is somewhat complex and best left to a computer, but it's notable that the WIF guarantees it will always correspond to the same address no matter which program is used to convert it.

	The Bitcoin address implemented using the sample above is: ~~1CC3X2gu58d6wXUWMffpuzN9JAfTUWu4Kj~~		The Bitcoin address implemented using the sample above is: 1CC3X2gu58d6wXUW{{taggant address}}MffpuzN9JAfTUWu4Kj

	==Mini private key format==		==Mini private key format==
			{{main\|Mini private key format}}
	Some applications use the [[mini private key format]]. Not every private key or Bitcoin address has a corresponding mini private key - they have to be generated a certain way in order to ensure a mini private key exists for an address. The mini private key is used for applications where space is critical, such as in QR codes and in [[physical bitcoins]]. The above example has a mini key, which is:		Some applications use the [[mini private key format]]. Not every private key or Bitcoin address has a corresponding mini private key - they have to be generated a certain way in order to ensure a mini private key exists for an address. The mini private key is used for applications where space is critical, such as in QR codes and in [[physical bitcoins]]. The above example has a mini key, which is:

	~~SzavMBLoXU6kDrqtUVmffv~~		SzavMBLoXU6{{taggant private key}}kDrqtUVmffv

	==Summary==		==Summary==
	Any Bitcoins sent to the address ~~1CC3X2gu58d6wXUWMffpuzN9JAfTUWu4Kj~~ can be spent by anybody who knows the private key implementing it in ''any'' of the three formats, regardless of when the bitcoins were sent, unless the wallet receiving them has since made use of the coins generated.		Any Bitcoins sent to the address 1CC3X2gu58d6wXUW{{taggant address}}MffpuzN9JAfTUWu4Kj can be spent by anybody who knows the private key implementing it in ''any'' of the three formats, regardless of when the bitcoins were sent, unless the wallet receiving them has since made use of the coins generated.
	The private key is only needed to spend the bitcoins, not necessarily to see the value of them.		The private key is only needed to spend the bitcoins, not necessarily to see the value of them.

	If a private key controlling unspent bitcoins is compromised or stolen, the value can only be protected if it is immediately spent to a different output which is secure.		If a private key controlling unspent bitcoins is compromised or stolen, the value can only be protected if it is immediately spent to a different output which is secure.
	Because bitcoins can only be spent once, when they are spent using a private key, the private key becomes worthless.		Because bitcoins can only be spent once, when they are spent using a private key, the private key becomes worthless.
	It is often possible, but inadvisable and insecure, to use the address implemented by the private key again, in which case the same private key would be reused.		It is often possible, but inadvisable and insecure, to use the address implemented by the private key again, in which case the same private key would be [[Address reuse\|reused]].

	==See Also==		==See Also==

← Older revision		Revision as of 06:07, 11 February 2019
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	==See Also==		==See Also==
			* [https://allprivatekeys.com/ Private keys directory and leaked keys database]
	* [[Paper wallet]]		* [[Paper wallet]]
	* [[How to import private keys]]		* [[How to import private keys]]