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SSH Key Converter: PPK to OpenSSH and Back
Convert a PuTTY .ppk key to OpenSSH format, or an OpenSSH or .pem key to PuTTY .ppk, without installing PuTTYgen. Paste your key or choose the file, and download the converted private and public keys.
PPK ↔ OpenSSHAWS .pem to .ppkEd25519, RSA & ECDSARuns in your browser
Remove the passphrase first: open the file in PuTTYgen, click Load, clear both Key passphrase boxes and click Save private key. Or convert it directly on Mac or Linux with puttygen key.ppk -O private-openssh -o id_ed25519.
Remove the passphrase first on a copy of the key with ssh-keygen -p -f copy_of_key (enter the old passphrase, then press Enter twice). Or convert it directly with puttygen id_ed25519 -o key.ppk.
Remove the passphrase first on a copy of the key with ssh-keygen -p -f copy_of_key.pem, or load it into PuTTYgen and save it as a .ppk.
Your key is converted in your browser and never uploaded. Still, only paste private keys into tools you trust, and never share them.
What it does
Three conversions in one tool
The converter detects the format automatically, shows the key type and fingerprint so you can confirm it’s the right key, and gives you the matching public key too. Keys protected with a passphrase need it removed first; the tool shows you exactly how.
With PuTTYgen
How to convert keys with PuTTYgen on Windows
Convert a .ppk to OpenSSH
- Open PuTTYgen and click Load.
- Change the file filter to All Files (*.*) if needed, and open your .ppk file.
- Go to Conversions → Export OpenSSH key.
- Save the file with no extension, for example
id_ed25519.
Convert OpenSSH or .pem to .ppk
- Open PuTTYgen and click Load.
- Choose All Files (*.*) and open your OpenSSH key or .pem file.
- Click OK on the import notice.
- Click Save private key and give it a .ppk name.
Command line
Convert keys on Mac and Linux with puttygen
Install the command-line version of PuTTYgen with sudo apt install putty-tools on Debian and Ubuntu, or brew install putty on a Mac. It also handles keys that have a passphrase.
PPK to OpenSSH private key
puttygen key.ppk -O private-openssh -o id_ed25519OpenSSH or .pem to PPK
puttygen id_ed25519 -o key.ppkGet the public key from a .ppk
puttygen key.ppk -O public-openssh -o id_ed25519.pubGet the public key from a .pem
ssh-keygen -y -f key.pem > key.pubPPK versions
PPK version 2 vs version 3
PuTTY 0.75 (released in 2021) introduced PPK version 3, which protects passphrase-encrypted keys with the stronger Argon2 algorithm. PuTTYgen now saves version 3 by default.
Older apps, including older versions of PuTTY, WinSCP and FileZilla, only understand version 2. If you’re not sure, version 2 works everywhere for keys without a passphrase.
Fixing “PuTTY key format too new”
This error means an older app is trying to open a version 3 .ppk file. Two easy fixes:
- Convert the key above and choose Version 2.
- In PuTTYgen, load the key, open Key → Parameters for saving key files, set PPK file version to 2, and save it again.
Or update the app: current versions of PuTTY, WinSCP and FileZilla read both formats. Looking for a newer client? See the best SSH clients.
Need a server?
Put your converted key to work
Most VPS hosts let you paste your public key when you create a server, so you can log in with PuTTY or OpenSSH right away.
DigitalOcean
Simple cloud servers with great docs. Add your SSH key when you create a Droplet.
From about $4/month
View DigitalOcean dealsHostinger
4 GB of RAM and NVMe storage on the entry VPS plan, with an easy control panel.
From about $6.49/month on a 24-month term
View Hostinger dealsRackNerd
Yearly KVM VPS deals for about the price of one month elsewhere. Great for learning.
From about $11/year on promo
View RackNerd dealsPrices are approximate. Compare all VPS hosts, including Vultr and ShockHosting.
FAQ
Key conversion questions, answered
Is it safe to convert my private key online?
This converter runs entirely in your browser, so the key is never sent to a server. That said, the safest option for keys that protect important servers is always to convert them on your own machine with PuTTYgen or puttygen.
What is the difference between .ppk and .pem files?
A .ppk file is PuTTY’s own key format. A .pem file is a standard text format used by OpenSSL and cloud providers like AWS. OpenSSH tools such as ssh, scp and Git can use .pem keys directly, while PuTTY needs a .ppk file.
Can I convert a key that has a passphrase?
Not in the browser. Remove the passphrase from a copy of the key first, or use PuTTYgen or the puttygen command, which can read and write passphrase-protected keys directly.
Does converting a key change it?
No. The key itself stays exactly the same; only the file format changes. The fingerprint before and after conversion is identical, so servers that trusted the old file will accept the new one.
Which key types are supported?
Ed25519, RSA and ECDSA (nistp256, nistp384 and nistp521) keys. Old DSA keys are not supported because modern SSH servers no longer accept them.
Where do I put the converted OpenSSH key?
Save it in your .ssh folder (~/.ssh on Mac and Linux, C:\Users\YourName\.ssh on Windows) and on Mac or Linux run chmod 600 on it so only you can read it.
Starting from scratch instead?
Learn how to create a new SSH key with ssh-keygen or PuTTYgen on Windows, Mac and Linux, step by step.