certpeek 2026.1.20

Peeks at certificates exposed by other hosts.

certpeek

Certpeek peeks at the certificates exposed by SSL/TLS enabled hosts. Perfect for a quick look for debugging.

And, it support tunneling through a HTTP proxy!

Usage:

Usage: certpeek [OPTIONS] HOST

  Peeks at certificates exposed by other hosts.

Options:
  --version          Show the version and exit.
  --proxy TEXT       Proxy to use.
  --servername TEXT  Custom SNI name to send in handshake.
  --no-servername    Do not send SNI in the handshake.
  --print-pem        Print certs in PEM format.
  --first-only       Only process the first retrieved cert.
  --openssl-format   Print cert info like OpenSSL.
  -h, --help         Show this message and exit.

Run it with uvx:

uvx certpeek google.no

Or install it permanently with either

uv:

uv tool install certpeek

pipx:

pipx install certpeek

or pip:

pip install certpeek