PuTTYgen

PuTTYgen, also known as PuTTY Key Generator is a component of PuTTY, a widely known free and open-source terminal emulator, serial console, and network file transfer application that is today used all over the world by advanced users.

It provides an added service to the complete PuTTY package by creating RSA and DSA keys for use with the OpenSSH authorized keys files.

While PuTTYgen 64 bit comes in a package with Telnet client and some other 3rd party software, some users require its standalone usage, and for them, creators of PuTTY have provided it as a standalone installation.

On its own, PuTTYgen is a very useful advanced networking and security tool that can create both public and private keys for many security standards, with advanced options for setting up the strength of the key and much more. One of the key strengths of this app is its simplicity, enabling power users to gain easy SSH authentication and generation of RSA and DSA keys with incredible ease.

The app features just a single simple UI screen, with a well-organized set of options and a built-in user manual that features well-documented usage scenarios for any type of user.

Features and Highlights

• Fully featured and RSA, DSA, ECDSA, and EdDSA key generation utility.
• Create a secure SSH authentication key in seconds.
• Streamlined interface, suitable for professionals who want quick and reliable key generation.
• Internal support for conversion into other formats.
• Support for passphrases.
• Available on all versions of Windows OS.
• 100% FREE!

Installation

PuTTYgen comes in an installation package that clocks in at a massive 640 MB, and therefore its transfer to the final hard drive location can last even a few minutes if your PC hardware is on a slower side (especially if you are using an old laptop with a slow storage drive).

However, the installation procedure is fairly straightforward, requiring you only to follow on-screen instructions. Full uninstaller is included in the package.

Once fired up, you will be welcomed with the minimalistic interface that features just a single screen that’s filled with tools and customization areas. At the bottom, you have the primary selection area where you must specify what kind of key you wish to generate. The options are RSA, DSA, ECDSA, ED25519, and SSH-1 (RSA).

Above that, you can customize the strength of the key, including the number of bits used (the higher the better) and the random data that is needed for the generation engine.

This random data is provided in an innovative way – by randomly moving the mouse cursor across the blank area of the app. This random movement data is incorporated into the key generation, ensuring that the key is completely unique. The key can be customized with a comment, and additionally secured with a passphrase.

The app can also convert the key into other formats if the default one does not suit your needs.

How to Use

• Launch PuTTYgen from the Start menu
• Choose the key type (RSA, DSA, ECDSA, etc.)
• Set the key size for security level
• Click "Generate" and move the mouse randomly
• Save the generated public and private keys
• Copy and use the public key for authentication
• Load an existing key for conversion if needed
• Protect the private key with a passphrase
• Use the key with PuTTY or other SSH clients

System Requirements

• Windows 7, 8, 10, 11 (32-bit or 64-bit)
• 1 GHz processor or higher
• 512 MB RAM or more
• 10 MB free disk space
• Internet connection for download

PROS

• Easy SSH key generation
• Supports multiple key formats
• Lightweight and fast
• Free and open-source
• Works with various SSH clients

CONS

• No built-in key management
• Lacks advanced security features
• Only a basic user interface
• No native macOS or Linux support
• Requires manual key conversion