How to Create SSH Keys on Windows and Log In to a Linux Server

Applies to: the OpenSSH client built into Windows 10, Windows 11 and Windows Server 2019 to 2025; Linux servers with OpenSSH

Windows includes the OpenSSH client, so you can create SSH keys and log in to a Linux server from PowerShell, without PuTTY. A key is safer than a password: the private key never leaves your computer.

1. Create the key

Open PowerShell (no administrator rights needed):

ssh-keygen -t ed25519 -C "you@laptop"

Press Enter to accept the location C:\Users\you\.ssh\id_ed25519, and set a passphrase. Microsoft’s documentation notes that Ed25519 is used when you don’t choose an algorithm. You get two files:

• id_ed25519: the private key. Keep it secret, like a password.
• id_ed25519.pub: the public key, which goes on the server.

2. Copy the public key to the Linux server

Windows has no ssh-copy-id. This one line does the same (you log in with the password one last time):

type $env:USERPROFILE\.ssh\id_ed25519.pub | ssh user@203.0.113.10 "mkdir -p ~/.ssh && chmod 700 ~/.ssh && cat >> ~/.ssh/authorized_keys && chmod 600 ~/.ssh/authorized_keys"

We ran the server-side part of this command for a test user: the key was added to ~/.ssh/authorized_keys with permissions 600, and the next login worked with the key.

3. Log in

ssh user@203.0.113.10
ssh -p 2222 user@203.0.113.10                       # if SSH uses another port
ssh -i $env:USERPROFILE\.ssh\other_key user@server  # a key with another name

Remember the passphrase with ssh-agent (optional)

The ssh-agent service is disabled by default. In PowerShell as administrator:

Get-Service ssh-agent | Set-Service -StartupType Automatic
Start-Service ssh-agent

Then, as your normal user: ssh-add $env:USERPROFILE\.ssh\id_ed25519.

Troubleshooting

• Permission denied (publickey): check that the public key is in ~/.ssh/authorized_keys of the same user you log in as, and that ~/.ssh is 700 and the file 600.
• ssh not found: add the optional feature OpenSSH Client in Windows Settings.
• Using PuTTY instead: connect with PuTTY.

After keys work, you can turn off password logins on the server: set up SSH keys for authentication and root login settings. Transferring files with the same key: SFTP.

Official documentation: Microsoft: key-based authentication in OpenSSH for Windows.