Honourable mentions

Directus

Directus is a popular choice for organizations that are looking for an open-source, self-hosted CMS. Unlike Strapi, Directus offers an unopinionated content model. Directus also has built-in SSO (SAML 2.0) and robust role-based permissioning features. However, as a relatively new CMS, they lack some features and capabilities that Sanity and Strapi currently offer (e.g., auto-save, third-party plug-ins and extensions).

Builder

Builder is a headless CMS with a built-in "what you see is what you get" (WYSIWYG) editor. The WYSIWYG editor allows users to create and manage content visually without having to write code, making it easier for non-technical users to change the website. Content authors can drag and drop pages and components without a developer.

They’re also relatively new and lack many features that other CMSes currently offer, but experienced and inexperienced teams alike will love its modern, user-friendly interface.