<p>From <a href="https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki" rel="nofollow noreferrer">BIP39</a>:</p>
<blockquote>
<p>The mnemonic must encode entropy in a multiple of 32 bits. With more entropy security is improved but the sentence length increases. We refer to the initial entropy length as ENT. The allowed size of ENT is 128-256 bits.</p>
</blockquote>
<p>Essentially, any random string of 128-256 bits can be converted into a BIP39 mnemonic.</p>
<p>However, if you're asking whether you can calculate a BIP39 mnemonic that would generate a given private key, that's not possible regardless of wallet scheme used because BIP39 specifies that to seed a wallet you need to run your mnemonic through a cryptographic hash function first.</p>

CC BY-SA 4.0
2021-09-10T11:05:55.157Z
Thanks for the info! New to this, just realized that
Trevor
CC BY-SA 4.0
2021-09-10T09:23:26.340Z
2022-09-25T12:59:10.173Z
2022-09-25T12:59:10.173Z
Vojtěch Strnad
<p>Can you turn a private key into Bip39?</p>
<p>private key example (just generated it, so it's empty): <code>xprv9s21ZrQH143K31B6HriXRx2YFmBjyvUA55YjK5c8bKBvqiGXaHKoSWMgK7xUdV7mdgsB4HiLfhsqqr6B3c3nzdyCvwFNFN8d1ZWe436yELa</code></p>
<p>Or should the key come from the Mnemonic entrophy string (also newly created &amp; empty)?
<code>e0b21dfb18343ead2254061b20eac319</code></p>

<mnemonic-seed>
Turning private keys into BIP39
Trevor
# Turning private keys into BIP39

(Asked by: username_0 on 2021-09-10)

Can you turn a private key into Bip39?

private key example (just generated it, so it's empty): `xprv9s21ZrQH143K31B6HriXRx2YFmBjyvUA55YjK5c8bKBvqiGXaHKoSWMgK7xUdV7mdgsB4HiLfhsqqr6B3c3nzdyCvwFNFN8d1ZWe436yELa`

Or should the key come from the Mnemonic entrophy string (also newly created & empty)?
`e0b21dfb18343ead2254061b20eac319`

**Tags:** mnemonic-seed


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## 1 answers

### Answer by username_1 on 2021-09-10. Score: 2 | Accepted answer

From [BIP39](https://github.com/bitcoin/bips/blob/master/bip-0039.mediawiki):

> The mnemonic must encode entropy in a multiple of 32 bits. With more entropy security is improved but the sentence length increases. We refer to the initial entropy length as ENT. The allowed size of ENT is 128-256 bits.

Essentially, any random string of 128-256 bits can be converted into a BIP39 mnemonic.

However, if you're asking whether you can calculate a BIP39 mnemonic that would generate a given private key, that's not possible regardless of wallet scheme used because BIP39 specifies that to seed a wallet you need to run your mnemonic through a cryptographic hash function first.

> **Comments:**
> **username_0**: Thanks for the info! New to this, just realized that  

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