Getting Started
New to OpenSSL? Start here. Installation, your first connection test, and understanding FIPS requirements.
OpenSSL FIPS Compliance Guide
18 minImplement FIPS 140-3 validated cryptography with OpenSSL 3.x. Learn FIPS capable vs compliant, configure the FIPS provider, and document for auditors.
How to Install OpenSSL
8 minInstall 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.
openssl s_client: TLS Testing Cheat Sheet + Fixes (2026)
10 minTest any TLS connection with openssl s_client. Copy-paste commands for SNI, cert chains, expiry, STARTTLS — and the hang everyone hits. Verified 2026.
Certificate Operations
Core certificate tasks with OpenSSL — each guide paired with an interactive demo where available.
Key Generation Commands
5 minGenerate RSA and EC private keys with OpenSSL. Common options and best practices.
CSR & Self-Signed Certs
6 minCreate CSRs and self-signed certificates with OpenSSL. Interactive and config file methods.
Inspect Certificates
5 minView certificate details with openssl x509. Extract subject, issuer, dates, and extensions.
Verify Certificate Chain
5 minValidate certificate chains with OpenSSL. Debug trust issues and missing intermediates.
Format Conversion
Convert between PEM, DER, and PKCS#12 formats using OpenSSL. Step-by-step commands for certificate format conversion.
Troubleshooting
Fix SSL certificate errors in Python, Git, and other tools that rely on OpenSSL under the hood.
Certificate Failure Scenarios
8 minCommon SSL/TLS errors and how to fix them. Expired certs, chain issues, name mismatches.
Git SSL Certificate Errors
15 minFix "SSL certificate problem: unable to get local issuer certificate" for clone, push, pull. Corporate proxy and self-signed cert solutions.
Python SSL Certificate Errors
10 minFix CERTIFICATE_VERIFY_FAILED in pip, requests, and conda. Corporate proxy solutions included.
Interactive Demos
Practice OpenSSL commands in your browser. No installation required — build commands visually and copy them to your terminal.
File Format Commands
Convert between PEM, DER, and PKCS#12 formats using OpenSSL. Step-by-step commands for certificate format conversion.
Key Generation
Generate RSA and ECC private keys with OpenSSL. Learn proper key sizes and security parameters for certificates.
Key Inspection & Matching
Inspect certificates with OpenSSL commands. View subject, issuer, validity, SANs, and extensions from the command line.
CSR & Self-Signed
Create Certificate Signing Requests with OpenSSL. Generate CSRs with SANs using config files and command line.
CSR Builder
Build a Certificate Signing Request step-by-step. Understand each CSR field and generate OpenSSL commands.
Related Videos
How to Install OpenSSL on Windows — Fix the PATH Error Too
Install OpenSSL on Windows and fix the "openssl is not recognized" PATH error that winget leaves behind.
RSA Encryption Explained
Understand the RSA algorithm that powers OpenSSL key generation and certificate signing.