Encryption for Everybody

A nonprofit providing free TLS certificates to more than 700M websites.

Explore our work to improve security and privacy

Our 2025 Annual Report highlights the progress we've made toward a better Internet.

From our blog

June 3, 2026 A Post-Quantum Future for Let's Encrypt

Let’s Encrypt is preparing its certificates for a post-quantum future through a new approach called Merkle Tree Certificates.

April 10, 2026 The difficulty of making sure your website is broken

Building automation to ensure having reliably invalid test certificates.

March 17, 2026 Simplifying Certificate Renewals for Millions of Domains with ACME Renewal Information (ARI)

ACME Renewal Information (ARI) helped Shopify make certificate renewals for millions of domains more reliable, scalable, and easier to manage.

Free, Automated TLS Certificates

Getting started

Let's Encrypt is a Certificate Authority that provides free TLS certificates, making it easy for websites to enable HTTPS encryption and create a more secure Internet for everyone. Let's Encrypt is a project of the nonprofit Internet Security Research Group.

Ready to begin?

Start securing your websites with free SSL/TLS certificates from Let's Encrypt. In order to get a certificate for your website's domain, you have to demonstrate control over the domain.

Global impact made possible by contributions

Support Encryption for Everybody

Your donation helps keep Let's Encrypt free and accessible to millions of websites around the world. Join us in securing the Internet, one site at a time. Every contribution makes a difference, whether you're an individual or a company.

Leading Through Sponsorship

Companies who rely on or value our work to encrypt the Web can financially support Let's Encrypt. Join companies big and small to make this work possible!

Let's Encrypt Growth

Certificates Active | Fully-Qualified Domains Active | Registered Domains Active

More ways we're improving security and privacy

Did you know Let's Encrypt has two sibling projects? Let's Encrypt and these two projects are operated by Internet Security Research Group (ISRG), a 501(c)(3) public benefit organization focused on making the Internet more secure and privacy-respecting.

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