---
title: "Let's Encrypt (SSL certificates)"
description: "Let's Encrypt is a free certificate authority issuing SSL/TLS certificates. Learn how the ACME protocol works and how certificates renew automatically."
url: "https://nodea.io/en/glossary/lets-encrypt-ssl-certificates"
lang: "en"
updated: "2026-07-13"
---

# Let's Encrypt (SSL certificates)

> Let's Encrypt is a free, open certificate authority (CA) that automatically issues and renews SSL/TLS certificates, enabling HTTPS-encrypted connections at no cost and without manual verification.

**Let's Encrypt** is a free, open and automated certificate authority (CA), launched in 2015 by the non-profit organization ISRG. It issues [SSL/TLS certificates](https://nodea.io/en/glossary/ssl) that enable encrypted connections over [HTTPS](https://nodea.io/en/glossary/https) — with no fees, formalities or manual verification. Its arrival significantly accelerated the spread of an encrypted internet.

## How Let's Encrypt works

The whole process is built on the **ACME** protocol (Automatic Certificate Management Environment), which automates issuing, installing and renewing certificates. It runs in a few steps:

- **domain validation** — the client proves control over the domain by placing a specified file or DNS record;
- **certificate issuance** — after successful validation the CA generates a DV (Domain Validation) certificate;
- **installation** — the certificate is placed on the server and assigned to the domain;
- **automatic renewal** — the client (e.g. Certbot) renews the certificate before it expires.

Certificates are valid for **90 days**, and this short lifetime combined with full automation is a deliberate design choice that reduces the risk associated with a possible key leak.

## Practical application

Let's Encrypt is today the default source of certificates in most hosting environments. Panels such as [DirectAdmin](https://nodea.io/en/glossary/directadmin), cPanel and Plesk issue and renew them with a single click, so enabling HTTPS on a site requires no technical expertise. DV certificates from Let's Encrypt are entirely sufficient for blogs, business sites and stores — a [hosting](https://nodea.io/en/glossary/hosting) plan with automatic SSL provides encryption and the trusted padlock symbol in the browser at no extra cost. For certificates covering all subdomains, the wildcard variant is used.

### Is a free Let's Encrypt certificate as secure as a paid one?

Yes, in terms of encryption strength a Let's Encrypt certificate is on par with paid DV (Domain Validation) certificates — it uses the same TLS standards. The differences concern additional services: commercial certificates may offer organization validation (OV/EV), financial warranties or technical support, which Let's Encrypt does not provide.

### How often does a Let's Encrypt certificate need renewing?

Let's Encrypt certificates are valid for 90 days, much shorter than commercial ones. This stems from the assumption of full automation — renewal is handled in the background by an ACME client (such as Certbot), usually after about 60 days. The process is hands-off, and the short lifetime limits the impact of a possible key compromise.

## Related

- [SSL](https://nodea.io/en/glossary/ssl)
- [HTTPS](https://nodea.io/en/glossary/https)
- [TLS](https://nodea.io/en/glossary/tls)
- [Hosting](https://nodea.io/en/glossary/hosting)
- [DirectAdmin](https://nodea.io/en/glossary/directadmin)

---

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