Master OpenSSL command-line tools. Key generation, CSR creation, certificate inspection, and chain verification.
Implement FIPS 140-3 validated cryptography with OpenSSL 3.x. Learn FIPS capable vs compliant, configure the FIPS provider, and document for auditors.
Install OpenSSL on Windows, Linux, macOS, and Alpine — plus why winget leaves it off your PATH and how to fix the 'openssl is not recognized' error.
Test any TLS connection with openssl s_client. Copy-paste commands for SNI, cert chains, expiry, STARTTLS — and the hang everyone hits. Verified 2026.
Generate RSA and EC private keys with OpenSSL. Common options and best practices.
Create CSRs and self-signed certificates with OpenSSL. Interactive and config file methods.
View certificate details with openssl x509. Extract subject, issuer, dates, and extensions.
Validate certificate chains with OpenSSL. Debug trust issues and missing intermediates.