Self-Signed Cert Command Generator

Generate openssl commands for creating self-signed SSL certificates for development and testing. Configure SAN (Subject Alternative Names), wildcards, and validity period for local HTTPS setup

Related Categories:Security

Certificate Fields

Common Name (CN)

Organization (O)

Organizational Unit (OU)

Locality (L)

State (ST)

Country (C)

Key Type

RSAEC

Key Size

2048 bit3072 bit4096 bit

Validity (days)

30d90d365d730d

Subject Alternative Names (SAN)

Generated Commands

One-liner

Generate private key and self-signed certificate in one command

openssl req -x509 -newkey rsa:2048 -keyout key.pem -out cert.pem -days 365 -nodes -subj "/CN=localhost"

Step 1: Generate RSA Private Key

Generate a 2048-bit RSA private key

openssl genrsa -out key.pem 2048

Step 2: Generate CSR

Create a Certificate Signing Request

openssl req -new -key key.pem -out csr.pem -subj "/CN=localhost"

Step 3: Self-Sign

Sign the CSR with the private key

openssl x509 -req -in csr.pem -signkey key.pem -out cert.pem -days 365

Verify Certificate

View the generated certificate details

openssl x509 -in cert.pem -text -noout

Verify Key

Check the private key

openssl pkey -in key.pem -check -noout