ssh-keygen
Using the ssh-keygen command, users can create, view, and manage SSH keys.
Create SSH Key
# Default (ED25519 recommended)
ssh-keygen -t ed25519 -C "[email protected]"
# RSA with 4096 bits
ssh-keygen -t rsa -b 4096 -C "[email protected]"
# Specify output file
ssh-keygen -t ed25519 -f ~/.ssh/my_key -C "[email protected]"View Fingerprint
ssh-keygen -lf ~/.ssh/id_rsa.pub
# As MD5
ssh-keygen -E md5 -lf ~/.ssh/id_rsa.pubView Public Key
cat ~/.ssh/id_rsa.pub
# Copy to clipboard (Linux)
cat ~/.ssh/id_rsa.pub | xclip -selection clipboard
# Copy to clipboard (macOS)
cat ~/.ssh/id_rsa.pub | pbcopyChange Passphrase
ssh-keygen -p -f ~/.ssh/id_rsaCopy Key to Server
ssh-copy-id -i ~/.ssh/id_rsa.pub user@hostKey Types Overview
| Type | Flag | Recommended |
|---|---|---|
| ED25519 | -t ed25519 | ✅ Yes |
| RSA | -t rsa -b 4096 | ⚠️ Legacy |
| ECDSA | -t ecdsa | ⚠️ Limited |
| DSA | -t dsa | ❌ Deprecated |
Tip
ED25519 is the recommended key type as it provides strong security with shorter key lengths compared to RSA.
Note
Your public key (*.pub) can be shared freely, while your private key should never be shared with anyone.