Yoonadev

Certificate Workbench

CSR Builder

Generate a Private Key & CSR

Generate a new Private Key and CSR entirely in your browser.

🔒 Local-only · No upload · No storage

Try an example

Example .test domains only. Generate creates a fresh key pair in your browser.

Subject Alternative Names

Use ASCII DNS names or punycode, including *.example.com. IP SANs are not supported by this builder. SANs are included only when entered.

Organization details (optional)

🔒 Private Keys never leave this browser.

Advanced information / extensions

Inputs and results are cleared when edited, cleared or when leaving this page. Copy and file saving happen only when you request them.

PEM text only · up to 1 MiB, 20 blocks, 128 KiB per block. DER, PFX/PKCS#12, JKS and encrypted keys are not supported in v1.

Usage guideWhen to use · How to use · Understand results

When to use this tool

Generate a new key pair and CSR when requesting a certificate for DNS names.

How to use it

  1. Enter Common Name, SANs and optional organization fields, then choose a supported key algorithm. Example filling does not generate a key.
  2. Generate, review the CSR, and explicitly save the private key somewhere safe before leaving the page.

Reading the result

Each generation creates a fresh key in the browser. Send the CSR to the issuer, not the private key. Yoonadev cannot recover the key after the page is closed.

Find a tool

↑ ↓ to select · Enter to open · Esc to close