Top 10 Best Certificate Authority Software of 2026

EJBCA is a leading open-source PKI Certificate Authority software that enables organizations to deploy scalable, enterprise-grade public key infrastructure for issuing, managing, and revoking digital certificates. It supports a wide array of protocols including ACME, CMP, SCEP, EST, and OCSP, along with advanced features like high-availability clustering, HSM integration, and compliance with standards such as ETSI TS 119 461. Widely used by governments, telecoms, and large enterprises, EJBCA excels in high-volume environments, handling millions of certificates with robust security and customization options.

Dogtag Certificate System is a robust, open-source enterprise PKI platform that enables the deployment of full Certificate Authority infrastructures, including subsystems for certificate issuance, revocation, key recovery, OCSP responding, and token processing. It supports high-availability setups, integrates with LDAP directories and Hardware Security Modules (HSMs), and provides a web-based administrative interface for managing the PKI lifecycle. Originally developed by Red Hat, it is widely used in government and large enterprise environments for secure certificate management.

OpenXPKI is a robust, open-source web-based Public Key Infrastructure (PKI) and Certificate Authority (CA) management system built on Perl. It excels in handling the full certificate lifecycle, including issuance, revocation, renewal, and validation through a highly customizable workflow engine. Designed for enterprise environments, it supports integration with Hardware Security Modules (HSMs), various cryptographic providers, and scalable deployments for high-volume operations.

Step CA from Smallstep is an open-source, lightweight certificate authority (CA) designed for operational public key infrastructure (PKI) management. It enables easy issuance, renewal, and revocation of x.509 certificates using the ACME protocol, compatible with tools like cert-manager, and integrates seamlessly with the step CLI for automation. Ideal for self-hosted deployments, it supports intermediates, online signing, and various backends like SQLite or PostgreSQL, emphasizing simplicity and security in dev, test, and production environments.

XiPKI is an open-source, Java-based PKI software suite that provides a high-performance Certificate Authority (CA), OCSP responder, and Time Stamping Authority (TSA). It supports extensive protocols including CMP, SCEP, EST, ACME, and REST APIs for certificate issuance, revocation, and management. Designed for scalability, it excels in enterprise environments requiring robust PKI operations with minimal resource footprint.

HashiCorp Vault is a robust secrets management platform with a dedicated PKI secrets engine that serves as a full-featured Certificate Authority for issuing, renewing, and revoking X.509 certificates dynamically. It supports multiple root and intermediate CAs, customizable templates, CRL distribution, and OCSP responders, all integrated with Vault's authentication and authorization systems. This makes it suitable for enterprise-scale automated certificate lifecycle management without manual intervention.

Microsoft Active Directory Certificate Services (AD CS) is a built-in Windows Server role that provides a full-featured public key infrastructure (PKI) for issuing, managing, and revoking digital certificates. It supports enterprise-scale certificate deployment for authentication, encryption, VPNs, Wi-Fi, and code signing within Active Directory environments. AD CS enables automated enrollment through Group Policy and integrates deeply with other Microsoft services for seamless PKI operations.

Keyfactor Command is an enterprise-grade platform for managing public key infrastructure (PKI) and digital certificates at scale. It automates the discovery, enrollment, issuance, renewal, and revocation of certificates across hybrid, multi-cloud, and on-premises environments. Supporting integration with multiple certificate authorities like Microsoft CA and Venafi, it ensures compliance, reduces outages, and streamlines security operations for large organizations.

Delinea Trust Protection Platform (TPP) is an enterprise-grade machine identity management solution focused on securing and automating the lifecycle of digital certificates, SSH keys, and code-signing certificates. It discovers, provisions, monitors, renews, and revokes certificates across on-premises, cloud, and hybrid environments, integrating with public and private CAs like Microsoft CA, Entrust, and DigiCert. TPP enforces policies for compliance, reduces risk from expired or vulnerable certificates, and supports DevOps integrations for scalable identity security.

AppViewX CERT+ is a certificate lifecycle management (CLM) platform that automates the discovery, monitoring, issuance, renewal, and revocation of digital certificates across on-premises, cloud, and hybrid environments. It integrates with multiple public and private Certificate Authorities (CAs), including support for deploying private PKI, providing enterprises with unified visibility and zero-touch automation to mitigate risks like expiration outages. As a CA software solution, it excels in streamlining PKI operations for large-scale deployments while ensuring compliance with standards like NIST and GDPR.