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🛡️ A private certificate authority (X.509 & SSH) & ACME server for secure automated certificate management, so you can use TLS everywhere & SSO for SSH.


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step-ca is an online certificate authority for secure, automated certificate management for DevOps. It's the server counterpart to the step CLI tool for working with certificates and keys. Both projects are maintained by Smallstep Labs.

You can use step-ca to:

  • Issue HTTPS server and client certificates that work in browsers (RFC5280 and CA/Browser Forum compliance)
  • Issue TLS certificates for DevOps: VMs, containers, APIs, database connections, Kubernetes pods...
  • Issue SSH certificates:
    • For people, in exchange for single sign-on identity tokens
    • For hosts, in exchange for cloud instance identity documents
  • Easily automate certificate management:

Comparison with Smallstep's commercial product

step-ca is optimized for a two-tier PKI serving common DevOps use cases.

As you design your PKI, if you need any of the following, consider our commerical CA:

  • Multiple certificate authorities
  • Active revocation (CRL, OSCP)
  • Turnkey high-volume, high availability CA
  • An API for seamless IaC management of your PKI
  • Integrated support for SCEP & NDES, for migrating from legacy Active Directory Certificate Services deployments
  • Device identity — cross-platform device inventory and attestation using Secure Enclave & TPM 2.0
  • Highly automated PKI — managed certificate renewal, monitoring, TPM-based attested enrollment
  • Seamless client deployments of EAP-TLS Wi-Fi, VPN, SSH, and browser certificates
  • Jamf, Intune, or other MDM for root distribution and client enrollment
  • Web Admin UI — history, issuance, and metrics
  • ACME External Account Binding (EAB)
  • Deep integration with an identity provider
  • Fine-grained, role-based access control
  • FIPS-compliant software
  • HSM-bound private keys

See our full feature comparison for more.

You can start a free trial or set up a call with us to learn more.

Questions? Find us in Discussions or Join our Discord.

Website | Documentation | Installation | Contributor's Guide


🦾 A fast, stable, flexible private CA

Setting up a public key infrastructure (PKI) is out of reach for many small teams. step-ca makes it easier.

⚙️ Many ways to automate

There are several ways to authorize a request with the CA and establish a chain of trust that suits your flow.

You can issue certificates in exchange for:

🏔 Your own private ACME server

ACME is the protocol used by Let's Encrypt to automate the issuance of HTTPS certificates. It's super easy to issue certificates to any ACMEv2 (RFC8555) client.

👩🏽‍💻 An online SSH Certificate Authority

  • Delegate SSH authentication to step-ca by using SSH certificates instead of public keys and authorized_keys files
  • For user certificates, connect SSH to your single sign-on provider, to improve security with short-lived certificates and MFA (or other security policies) via any OAuth OIDC provider.
  • For host certificates, improve security, eliminate TOFU warnings, and set up automated host certificate renewal.

🤓 A general purpose PKI tool, via step CLI integration


See our installation docs here.