CSR & OpenSSL Command Generator
Generate Certificate Signing Requests (CSR) and zero-trust OpenSSL CLI commands with Subject Alternative Names (SANs).
openssl req -new -newkey rsa:2048 -nodes -keyout example.com.key -out example.com.csr -subj "/C=US/ST=California/L=San Francisco/O=Acme Global Technologies Inc./OU=Security & Operations/CN=example.com" -addext "subjectAltName=DNS:example.com,DNS:www.example.com,DNS:api.example.com"
Understanding SSL Public Key Infrastructure (PKI)
Public Key Infrastructure relies on an asymmetric key pair: a private key that remains confidential on your server, and a public key enclosed within the Certificate Signing Request. When a trusted Certificate Authority signs your CSR, they validate your domain ownership and issue a public certificate establishing end-to-end encrypted HTTPS channels.
Security Applications
- ✓Commercial SSL / TLS Certificate Procurement
Generate compliant CSR payloads required by commercial Certificate Authorities (DigiCert, Sectigo, GlobalSign, GoDaddy) for OV and EV SSL certificates.
- ✓Multi-Domain SAN & Wildcard Certificates
Configure Subject Alternative Names (SANs) so a single SSL certificate validates your root domain, subdomains (`api.`, `app.`), and wildcard paths.
- ✓DevSecOps Zero-Trust Terminal Workflows
Produce exact, copy-pasteable OpenSSL terminal one-liners that generate the private key directly on your secure server so secrets never touch a browser.
- ✓NGINX & Apache HTTPS Server Hardening
Standardize cryptographic algorithms across enterprise infrastructure with modern 2048-bit or 4096-bit RSA keys and modern ECDSA elliptic curves.
Key Capabilities
OpenSSL Terminal One-Liner Generator
Produces verified `openssl req -new` terminal commands that bundle Subject strings and `subjectAltName` extensions into a single command.
OpenSSL Configuration (.cnf) Export
Download pre-formatted `.cnf` configuration files for non-interactive automated provisioning scripts and CI/CD pipelines.
Multi-Domain SAN Extension Support
Properly formats RFC 5280 Subject Alternative Names to ensure modern browsers (Chrome, Safari, Firefox) accept your certificate without warnings.
Zero-Trust Architecture
Empowers engineers to keep private keys securely confined to their own local environment without exposing them over the network.
Frequently Asked Questions
What is a Certificate Signing Request (CSR)?
A CSR is a block of encoded text that is sent to a Certificate Authority (CA) when applying for an SSL/TLS certificate. It contains public key cryptography information and identifying details about your organization and domain name.
Why does modern SSL require Subject Alternative Names (SANs)?
Major web browsers (including Google Chrome and Safari) have deprecated matching hostnames against the legacy Common Name (CN) field. Modern security standards mandate that all valid hostnames must appear inside the `subjectAltName` (SAN) extension.
Should I choose RSA 2048, RSA 4096, or ECDSA?
RSA 2048-bit is the industry benchmark supported by 100% of legacy and modern clients. RSA 4096-bit offers stronger security at the cost of slightly higher CPU latency during TLS handshakes. ECDSA (prime256v1) provides equivalent security with smaller keys and faster performance.
Where is my private key stored when using this tool?
By utilizing the generated OpenSSL terminal command, your private key (`.key`) is generated locally on your own computer or server and never leaves your hard drive, ensuring 100% security compliance.
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