Ajv vs JSON OS

Ajv has no write-up on Specifiction yet; its figures are above.

JSON OS is a free, browser-based workbench that pairs a JSON editor with Markdown Studio, a Markdown previewer. The maker says it needs no signup and that processing runs locally in a Web Worker, with data stored in IndexedDB and nothing leaving the device. The JSON workspace supports up to three panes and can open or accept dropped files. Data can be viewed and edited as a tree, text or table, with table columns switched independently. The editor formats, beautifies, minifies and sorts JSON keys, validates against JSON Schema with Ajv format checks, and repairs malformed input such as smart quotes, comments and unclosed brackets. It compares two documents side by side and supports MongoDB-style filters; JSON arrays can be exported to CSV with a UTF-8 BOM. Markdown Studio supports GitHub-Flavored Markdown, Mermaid, KaTeX, highlighted code and embeds from services including YouTube, Vimeo and GitHub Gist. It sanitizes rendered HTML through DOMPurify, stripping scripts and untrusted iframes. Markdown can be exported as source, copied as rendered HTML or downloaded as standalone HTML.