Summary:
Use a Public CA when you need certificates for public-facing websites, customer applications, or any service accessed by external users, as public CAs are automatically trusted by all browsers and devices. Use a Private CA when securing internal networks, development environments, IoT devices, or any infrastructure where certificates only need to be trusted within your organization. Most enterprises need both: public CAs for external-facing services and private CAs for internal infrastructure, best managed through a unified certificate lifecycle management platform.
Consider weaving in CA-agnostic capabilities in the setup and conclusion as AppViewX is CA agnostic eliminating the threat of vendor locking.
Key Differences:
| Aspect | Public CA | Private CA |
| Best For | Public websites, customer-facing apps, external APIs | Internal networks, DevOps, IoT, employee authentication |
| Trust | Automatic browser/device trust | Manual trust deployment required |
| Cost Model | Pay per certificate | Setup cost + unlimited issuance |
| Certificate Transparency | Required (public logs) | Not required (privacy maintained) |
| Ideal Volume | Low to medium volumes | High volume needs (1000+ certificates) |
| Control | Limited customization | Full policy control |
Understanding Certificate Authorities (CAs): The Foundation of PKI
What is a Public Certificate Authority?
A Public Certificate Authority (CA) is a trusted third-party organization that issues SSL/TLS certificates for websites and applications accessible on the public internet. Public CAs are recognized and trusted by all major browsers and operating systems.
When you purchase an TLS certificate for your public-facing website, you’re obtaining it from a public CA that has been vetted and included in browser trust stores. These certificates enable the HTTPS connections users see when visiting secure websites.
What is a Private Certificate Authority?
Organizations often need to secure their internal infrastructure, applications, and users with digital certificates. When an organization establishes the capability to issue these certificates internally, it becomes a Private Certificate Authority. Private CA creates certificates that are only trusted within the organization’s own environment.
Which type of CA is right for your organization
The decision between Private CA and Public CA isn’t about choosing the “best” solution, it’s about matching your certificate infrastructure to your organization’s specific needs, scale, and growth trajectory. With the PKI market projected to reach USD 24.37 billion by 2032, growing at 20.1% annually, and Cloud/Managed PKI solutions expanding at 21.3% CAGR, you’re making this decision in a landscape where automation and scalability are no longer optional, they’re business necessities and competitive advantages.
Your path forward starts with understanding where certificates fit in your architecture today and where they need to take you tomorrow. Organizations currently manage thousands of internal certificates, yet still rely on spreadsheets for tracking. If that sounds familiar, you’re not behind, you’re at the perfect inflection point to build a certificate strategy that scales with your business rather than against it.
Public CA makes sense when you need immediate, universal trust. If your certificates protect customer-facing websites, e-commerce platforms, or services that external parties must validate, Public CA ensures trust through pre-installed root certificates in browsers and operating systems.
Private CA unlocks flexibility and scale for internal operations. When you’re securing internal applications, service-to-service communication, VPN access, or IoT device authentication, Private CA lets you define your own certificate policies, validity periods, and issuance workflows.
Automation for Public and Private CAs
The shift to automated certificate lifecycle management isn’t just about keeping pace with industry changes, it’s about positioning your organization to move faster and maintain digital trust. With recent CA/Browser Forum changes and a timeline that leads to 47-day certificate validity by March 2029 and machine identities growing 20 times faster than human identities, the organizations that automate today gain operational agility that compounds over time.
AVX ONE accelerates your automation journey. AppViewX helps companies manage their Certificate Authorities (CAs) by providing powerful certificate lifecycle management (CLM) solutions that automate, unify, and secure certificate operations across both public and private CAs in hybrid and multi-cloud environments. Rather than building custom integrations or managing multiple point solutions, it provides enterprise-grade certificate lifecycle automation that delivers results from day one.
The platform discovers certificates across your entire infrastructure regardless of issuer, automates end-to-end workflows from CSR (Certificate Signing Request) generation through deployment, and provides unified visibility across hybrid and multi-cloud environments.