Online multi-domain certificate signing request generator

UPDATE: This tool has become so popular on my blog that I’ve updated it, cleaned it up, added some new features, and released it under its own domain. Try it out at

I developed this tool because I could not find any other online certificate signing request generators that supported multiple common names (CNs) and multiple subject alternative names (SANs). It is likely that you would not want to use this tool to create CSRs for a production environment because it sends the private key over the internet, but it also shows the openssl command that can be used on a linux system to generate the CSR and private key. It greatly simplifies writing what can be a very long, complicated command when using multiple CNs and multiple SANs.

The output will be displayed below the form after clicking submit.


  • Easily get the certificate of any internet accessible https site
  • Create certificate signing requests (CSRs) and private keys
  • Use existing certificates as templates for CSRs
  • Generate the openssl commands used for each operation to be used offline
  • Use output to send to a trusted certificate authority (CA) to be signed
  • Support for multiple domains
  • Support for wildcard certificates
  • Enter as many subject alternative names (SANs) and common names (CNs) as you want
  • Generate 2048 bit or 4096 bit keys

After generating your certificate signing request, you can submit it to one of many Root Certificate Authorities like or

Certificate AttributesUse an existing certificate as a template
Common Name(s):
Alternative Name(s):
Locality (City):
CAPTCHA Image [ Different Image ]