Format, validate, and minify JSON data. Pretty-print with proper indentation.
This is an all-in-one JSON formatter, validator, beautifier, viewer, and minifier. Paste raw or minified JSON into the input area and click <strong>Format</strong> to pretty-print it with proper 2-space indentation and syntax-highlighted output (the same view a JSON viewer or JSON beautifier would give you). Use <strong>Minify</strong> to compress JSON by removing all unnecessary whitespace, ideal for reducing payload size in APIs and configuration files. The <strong>Validate</strong> button checks whether your input is valid JSON and provides detailed error messages with line numbers when syntax issues are found. All processing is performed entirely in your browser, so your data never leaves your device.
When you paste a long or deeply nested JSON document, the formatted output renders with syntax highlighting — keys, strings, numbers, booleans, and nulls each get their own color so the structure is easy to scan. This makes the tool a practical JSON viewer for inspecting API responses, debugging webhook payloads, or reading log entries that embed JSON. Combined with formatting, you get the readability of a dedicated JSON viewer plus the cleanup of a JSON beautifier in one paste.
The JSON validator surfaces specific problems instead of a generic "invalid" message. Common JSON errors it catches: trailing commas (not allowed in strict JSON), single quotes around strings (JSON requires double quotes), unmatched brackets or braces, unescaped newlines or tabs inside strings, missing commas between object properties or array elements, and unquoted object keys. Each error includes the line number so you can jump straight to the broken token. JSON does not support comments — if you need them, consider JSON5 or JSONC.
Pretty-print and beautify JSON with consistent 2-space indentation. Minify JSON for production use and reduced payload size. Validate JSON syntax with line-level error messages. Syntax highlighting via highlight.js for a clean JSON viewer experience. Copy formatted or minified output to clipboard with one click. No server-side processing, no data collection, no sign-up required — runs entirely client-side and works offline once loaded.
These names describe overlapping features of the same tool. A JSON formatter or beautifier pretty-prints raw or minified JSON with consistent indentation so it is human-readable. A JSON viewer adds syntax highlighting and structural display (collapsible objects/arrays). A JSON validator checks whether the input is syntactically valid JSON and reports specific errors with line numbers. A JSON minifier does the opposite of formatting — strips all whitespace to produce a compact single-line payload. This tool does all four.
Paste your minified JSON (e.g., from an API response or log file) into the input area and click Format. The output panel shows the pretty-printed version with 2-space indentation and syntax highlighting. Click Copy to grab the result. The reverse — Minify — collapses formatted JSON back to a single compact line for production use.
Click Validate. The validator parses your input and reports specific error messages — missing commas, unmatched brackets, trailing commas, single quotes used instead of double quotes, unescaped newlines in strings — with the line number where the parser failed. Common gotchas: JSON requires double quotes (not single), forbids trailing commas after the last array/object element, and does not allow comments.
Yes. All formatting, validation, and minification happens entirely in your browser using JavaScript's native JSON.parse() and JSON.stringify(). Nothing is sent to any server. The page works offline once loaded — safe for sensitive API responses, configuration files with secrets, or production payloads.
A modern code editor with live preview, built for web developers and designers.
Try Phoenix Code Free