🪄 Using a Self-Signed SSL Certificate

Fine for testing and dev — never for production. Here's why.

Here's what to know when generating and using a self-signed certificate to test HTTPS in a local dev environment.

What a self-signed certificate is

It's a certificate signed by the issuer itself rather than a public certificate authority (CA). Since this issuer isn't registered in a browser's trust store, connecting triggers a warning like "Your connection is not private."

Why it doesn't belong in production

Showing visitors a security warning every time erodes trust on its own, and getting users into the habit of clicking past browser warnings makes a real man-in-the-middle attack harder to notice. A live service should use a real CA-issued certificate — a free one from Let's Encrypt, for instance.

Using it without warnings in local dev

Registering the generated self-signed certificate directly into your OS or browser's trust store (macOS Keychain Access, Windows Certificate Manager, etc.) removes the warning in your local environment. A tool like mkcert automates that registration step.

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