How Let's Encrypt and DigiCert differ on deployment, pricing, openness and what each is actually built for.
| Let's Encrypt | DigiCert | |
|---|---|---|
| Type | Public CA (free) | Public CA + CLM |
| Deployment | SaaS (ACME) | SaaS |
| How it works | Issues domain-validated TLS certificates at no cost, exclusively through the ACME protocol. Short 90-day lifetimes force automation, which is the point: renewal is a cron job, not a calendar reminder. | Issues publicly trusted TLS, code-signing, S/MIME and document-signing certificates from its own roots. DigiCert ONE adds discovery, automation and policy enforcement across the estate, with ACME and REST APIs for issuance. |
| Pricing* | Free | From $218/yr (Basic OV) |
| Free tier | Yes | No |
| Open source | Boulder (MPL-2.0) | — |
| Compliance | WebTrust, CA/B Forum | WebTrust, CA/B Forum, FIPS 140-2 (HSM-backed) |
| Best for | Public web TLS on anything you can automate | Enterprises needing public trust plus governance |
Choose Let's Encrypt for public web tls on anything you can automate. Choose DigiCert for enterprises needing public trust plus governance.
* Indicative list pricing (vendor documentation and public pricing pages, August 2026).