Sanity is a headless content management system (CMS) made by Sanity, which calls it a Content Operating System. A headless CMS stores and edits content but does not render the website; the site's own code fetches the content through an API and displays it.
Content is stored in the Content Lake, Sanity's hosted real-time database for structured content. Developers define content types as schemas in code, and editors work in Sanity Studio, an open-source editor built with React that the team can configure and that Sanity hosts free of charge. A website queries the content with GROQ, Sanity's query language, or with GraphQL, and receives it through a global content delivery network (CDN); an image pipeline delivers the images. Other features are live previews and visual editing, revision history for every document, scheduled content releases, functions that react to content events, and AI agents that edit, translate or audit content in bulk.
Sanity is a hosted service with a Free plan and paid plans billed per user seat each month; usage above the included quotas is billed by use.