> For the complete documentation index, see [llms.txt](https://www.kryptor.co.uk/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.kryptor.co.uk/tutorial/key-pair-options.md).

# Key pair options

## Recovering your public key

If you've lost/forgotten your public key, Kryptor can regenerate it for you from your private key. The public key string will be displayed, and a `.public` key file will be created if one doesn't exist in the same directory as the specified `.private` key file.

Here's an example:

```bash
$ kryptor -r -x:"C:\Users\samuel-lucas6\.kryptor\signing.private"

Enter your private key passphrase:

Decrypting private key...

Public key: Ed//L2CzmImpu9UA6HFjllemS4TVaE84PdTTrTNc5i6gxFU=
Public key file: "C:\Users\samuel-lucas6\.kryptor\signing.public"
```

## Changing your private key passphrase

Kryptor will re-encrypt your private key using a new passphrase, overwriting the previous encrypted private key file.

Here's an example:

```bash
$ kryptor -m -x:"C:\Users\samuel-lucas6\.kryptor\encryption.private"

Enter your private key passphrase:

Decrypting private key...

Enter a passphrase (leave empty for a random one):

Retype passphrase:

Deriving encryption key from passphrase...
Passphrase changed successfully.
```


---

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