Generate self-signed certificate

Certificates for local development or testing
GENERATE
Certificate
Private key

About this tool

Generate a self-signed certificate and matching private key by entering a domain, validity period, and RSA key size. Download the PEM outputs for local development or testing. Browsers and clients will not trust a self-signed certificate by default, so it is not suitable for a public production website.
Available via the API.

Limits

Limited to 10 requests / day when used without registration.
Get more when you sign up (it's free) or buy a plan.
Plan Free - 1 000 requests / month
Plan Plus - 10 000 requests / month
Plan Pro - 100 000 requests / month
Plan Max - 300 000 requests / month
Learn more about plans and pricing.

Tips

  • Use self-signed certificates only for local development, testing, and internal applications and never for production or public-facing websites.
  • Browsers will display security warnings for self-signed certificates. This is expected and normal for non-production use.
  • Use longer validity periods for development certificates to avoid frequent regeneration.
  • Create wildcard certificates by using an asterisk (*) in the domain name.

Frequently Asked Questions

  • What is a self-signed certificate?

    A self-signed certificate is an SSL/TLS certificate that is signed by its own creator instead of a trusted Certificate Authority. It enables encrypted HTTPS connections but is not automatically trusted by browsers.

  • Why does my browser show a warning for self-signed certificates?

    Browsers cannot verify the certificate against a trusted authority, so they display a security warning. This is expected and not a sign of a problem for local development or internal use.

  • Can I use a self-signed certificate in production?

    No, self-signed certificates should be used only for local development, testing, and internal applications. Use a certificate from a trusted Certificate Authority for public-facing websites.

  • Is my certificate data stored after generation?

    Generated certificates and keys are created to be returned to you and are not kept for purposes other than delivering your output.

  • Is the tool free to use?

    Yes, you can generate a limited number of certificates without an account. Creating an account or upgrading your plan increases your usage limits.

Something missing?

Feel free to contact us if you have any suggestions or found a bug.

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