OpenSSL & Certnew

OpenSSL Command Builder

Free online OpenSSL command builder. Generate OpenSSL commands visually for common tasks including generating keys, creating CSRs, signing certificates, converting formats, inspecting certificates, and testing SSL connections. Perfect for developers and sysadmins who need OpenSSL commands without memorizing complex syntax. Copy the generated command and run it directly in your terminal.

Check SSL Certificate (live)

Inspect SSL cert of a live server

GENERATED COMMAND
echo | openssl s_client -connect example.com:443 -servername example.com 2>/dev/null | openssl x509 -noout -text

💡 OpenSSL is pre-installed on Linux and macOS. Windows: use Git Bash, WSL, or download from slproweb.com

how to use

  1. 1.Select the OpenSSL operation you want to perform
  2. 2.Fill in the required parameters
  3. 3.Copy the generated command
  4. 4.Run it in your terminal

frequently asked

Do I need OpenSSL installed?

Yes — this tool generates commands for you to run locally. OpenSSL is pre-installed on most Linux/macOS systems. Windows users can install it via Git Bash, WSL, or the OpenSSL installer.

What operations are supported?

Key generation, CSR creation, self-signed certs, format conversion (PEM/DER/PFX), certificate inspection, SSL connection testing, and more.

Are the commands safe to run?

Yes — all generated commands use standard OpenSSL syntax. Always review the command before running, especially when specifying file paths.