JSON OS vs JSONBuddy

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.

JSONBuddy provides tools for editing, validating, formatting, transforming, and automating JSON and JSON Schema work. Its Windows editor offers text and grid views, schema-aware completion, and validation results. Schema tools include authoring assistance, reference navigation, diagnostics, debugging, analysis, tests, and documentation. Validation checks JSON syntax and schema constraints, with reports linking failing data to relevant rules. The product converts among JSON, CSV, XML, and HTML, including CSV imports and JSON-to-CSV output. Streaming validation can process large JSON without loading the entire document into memory; streaming JSON Schema validation through -jsv requires a JSONBuddy Large Data license. Windows command-line tools support repeatable checks in scripts and CI, and the published Core API v1 supports formatting, minifying, JSON Patch, validation, and schema documentation. ValBuddy CLI performs file operations locally on Windows and can return selected diagnostics to an AI agent, though selected content or diagnostics may be sent to its model provider. Licenses include free personal and educational use and paid perpetual options, starting at $15 for JSONBuddy Swift. The portable package requires 64-bit Windows 10 or 11.