Generate CSR and private key entirely in-browser. Free CSR generator online.
A CSR (Certificate Signing Request) generator creates the request and key pair you need to obtain an SSL certificate from a Certificate Authority (CA). This tool runs entirely in your browser: the private key never leaves your device, which is important for security. You enter the domain name (Common Name), organization details, and optionally Subject Alternative Names (SANs) for multi-domain certs. The generator produces a PEM-encoded CSR and a private key (usually RSA or ECDSA). You submit the CSR to your CA (e.g. Let's Encrypt, DigiCert, Sectigo); the CA signs it and returns the certificate. You then install the certificate and the private key on your server. Generating the key in-browser avoids transmitting the key over the network. Always keep the private key secure and never share it.
A Certificate Signing Request contains the public key and identity info you want on the certificate. The CA signs it to create your cert.
So the private key is generated and stays on your machine. You only send the CSR (no private key) to the CA.
Both are supported. ECDSA keys are smaller and often faster; RSA is more widely supported. Check your server and CA support.
Yes. Add them as SANs (Subject Alternative Names) in the generator so one certificate can cover several hostnames.
Store it securely on the server that will use the certificate. Never send it to the CA or expose it publicly.