JSON Tools
Formatting, validating, diffing and converting JSON. The recurring question is not "is this valid JSON" but "why does this structurally identical document fail to diff cleanly" — usually key order or number formatting.
Comparisons here are semantic where possible: key order is ignored, so a reordered object does not show up as a change.
- CSV to JSON and BackConvert between CSV and JSON both ways. Detects comma, semicolon, tab and pipe delimiters and handles quoted commas and newlines correctly.
- JSON Diff
- JSON Formatter and ViewerFormat, validate and minify JSON with 2/4-space or tab indentation, optional key sorting and a collapsible tree view. Syntax errors are reported with line and column.
- JSON to Code TypesTurn JSON or a JSON Schema into type definitions for 26 languages including TypeScript, Go, Java and Python. Comments and trailing commas are fine and everything runs in your browser.
- JSON to HTML table converterConvert JSON to HTML table and back. Object arrays become a <table> with thead/tbody; HTML tables parse into arrays of objects, with smart number detection and XSS-safe escaping. Fully local.
- JSON to Markdown TableConvert between JSON and Markdown tables, with nested expansion, column alignment and special-character escaping. Fully offline.
Guides in this category
Common questions
Why does my JSON fail to parse after an edit?
Trailing commas, single quotes and unquoted keys are legal in JavaScript objects but not in JSON. The validator points at the exact offset.