Best Free SSL Certificates 2026: 6 Options Compared

Free SSL certificates are widely available, and for most sites they are as good as paid ones for encrypting traffic. Let's Encrypt, run by the nonprofit Internet Security Research Group, offers certificates at zero cost to anyone who owns a domain name. ZeroSSL has a free plan with three 90-day certificates and ACME support, with paid plans from $14.99 a month. Most people do not request certificates by hand; they use an ACME client. Certbot from the Electronic Frontier Foundation is the usual choice, acme.sh is a pure Unix shell alternative with few dependencies, and Caddy gets and renews certificates automatically as a web server. Cloudflare's free plan includes universal SSL if you put your site behind it, which solves certificates for visitors without managing any yourself. The trade-offs are short lifetimes and what a free certificate does not give you. Free certificates are 90 days long, so automated renewal is not optional. They prove control of a domain, not the identity of the business, so if you need a warranty or organization validation, you must pay. Test renewal in a staging environment before relying on it, and set an alert for expiry in case the automation fails.

Let's Encrypt

Free certificates for anyone who owns a domain name, run by the nonprofit ISRG. The default choice for most websites; certificates are short-lived and need automated renewal.

Price: Free (Free certificates for anyone who owns a domain name; run by the nonprofit ISRG) (Let's Encrypt pricing, checked 2026-10-23).

Platforms and license: Any server with an ACME client. Service (free CA).

Best for: Almost any website.

ZeroSSL

Free plan includes 3 90-day certificates, with ACME and wildcard listed as free features. Paid Basic is $14.99 a month billed yearly. Has a web dashboard if you dislike command lines.

Price: Free (Free plan: 3 90-day certificates; ACME and wildcard listed as Free features, wildcard quantity not stated); paid from $14.99 per month, billed yearly (Basic) (ZeroSSL pricing, checked 2026-10-23).

Platforms and license: Web dashboard, ACME. Proprietary SaaS.

Best for: Users who want a dashboard as well as ACME.

Certbot

Apache-2.0 ACME client from the EFF. Free; automates getting and renewing certificates on a server you control, with plugins for common web servers.

Price: Free (Free open-source software) (Certbot pricing, checked 2026-10-23).

Platforms and license: Linux, macOS, Windows. Apache-2.0 (open source).

Project activity: 33.3k GitHub stars · latest release v5.8.0 (Sep 1, 2026) · last commit Oct 27, 2026

Best for: Servers where you want automated renewal.

Worth knowing: Licence read from LICENSE.txt. Certbot itself is free; the certificate authority it uses sets its own terms.

acme.sh

GPL-3.0 pure Unix shell ACME client. Light on dependencies and runs almost anywhere with a shell; fewer guardrails than Certbot.

Price: Free (Free open-source software) (acme.sh pricing, checked 2026-10-23).

Platforms and license: Unix shell. GPL-3.0 (open source).

Project activity: 47.9k GitHub stars · latest release 3.1.6 (Sep 20, 2026) · last commit Oct 23, 2026

Best for: Minimal servers and scripts.

Worth knowing: Pure Unix shell ACME client per the repo description.

Caddy

Apache-2.0 web server with automatic HTTPS per the repo description. Certificates are handled without extra tools, though you must use Caddy as your web server.

Price: Free (Free open-source software) (Caddy pricing, checked 2026-10-23).

Platforms and license: Linux, macOS, Windows, BSD. Apache-2.0 (open source).

Project activity: 78.5k GitHub stars · latest release v2.11.7 (Oct 3, 2026) · last commit Oct 27, 2026

Best for: New sites where you can choose the server.

Worth knowing: Web server with automatic HTTPS per the repo description.

Cloudflare

Free plan includes universal SSL along with DNS, DDoS protection and CDN; Pro is $20 a month billed annually. Requires routing your traffic through Cloudflare.

Price: Free (Free plan: DNS, unmetered DDoS protection, CDN, universal SSL, WAF managed ruleset); paid from $20 per month, billed annually (Pro; $25 billed monthly) (Cloudflare pricing, checked 2026-10-22).

Platforms and license: Web. Proprietary.

Best for: Sites that want a certificate without managing one.

Worth knowing: Business plan is $200/month billed annually ($250 monthly). Free plan has community support only and no uptime SLA.

Compare: Cloudflare alternatives

Which one to pick

• You run a normal web server: Certbot
• You want automatic HTTPS from the web server itself: Caddy
• You want a managed solution: Cloudflare
• You prefer a dashboard: ZeroSSL