Self-Signed Certificate & Local CA Generator
Generate self-signed certificates or a local development CA and a warning-free localhost certificate — keys stay in your browser.
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Frequently Asked Questions
Browsers only trust certificates from known CAs. Generate a local CA, trust it once on your machine, and certificates it signs will load without warnings.
Up to 10 years for a CA. Server certificates signed by the local CA are capped at 825 days because Apple devices reject longer ones.
Not for public websites — use a real CA such as Let's Encrypt. Local CAs are ideal for development, internal tools and testing.
Open the OpenSSL commands tab: the Trust a local CA section has one-line commands for macOS, Windows, Ubuntu, Fedora and Node.js.