The tool

The JSON workbench: one document, several perspectives

Paste, drop or load a JSON file: the editor, validation, tree, table, queries, diff and conversion all stay right on your device.

JSON Formatter & JSON Toolkit

Online Development, Code & Data

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Real-time validation Format on paste

Recursive sorting makes diffs reproducible: two files containing the same keys in a different order produce an identical result. Formatting never changes the data values — it can only change the display order.

JSON input

Output

Drop a .json / .jsonc / .json5 / .ndjson / .jsonl / .har file here, or click to choose a file. 100% local import.

Examples:

JSON to validateRFC 8259 engine + linter

Click an error to locate it in the source text (line, column, offset and snippet are shown).

The linter accepts sloppy JSON (trailing comma, unquoted keys, single quotes, comments…), but it flags these deviations: a real RFC 8259 parser would reject them. The validation engine always makes the distinction and shows the expected token and the encountered token for each error.

Broken / sloppy JSON

Safe repair: only fixes unambiguous errors (BOM, trailing comma, single quotes, unquoted keys, undefined/NaN/Infinity, comments…). Aggressive repair: tries to recover as much data as possible (missing braces/brackets/commas, unbalanced parentheses).

Result + mini-diff

Source

Large documents are rendered progressively (subtrees are materialized only when opened) — the interface stays responsive up to the limits of the browser memory. Hover a value to copy its full path or JSON Pointer.

Source (array of objects)

Automatic detection finds the first array of objects. Click a column to sort, click again to reverse. CSV/TSV/Markdown export ready to paste into a spreadsheet.

Source

RFC 9535-compliant engine: recursive descent $.., wildcard .*, slices [start:stop:step], unions [0,2] and filters [?(@.age > 18)]. Snippets:

Source

JSON Pointer (RFC 6901): /users/0/profile/email. Standard addressing scheme used by JSON Patch and APIs. You can also convert a JSONPath expression to a pointer when the mapping is direct.

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JSON A (reference)

JSON B (compared)

Source

Conversion—

Conversions generated locally, no network library involved. YAML, XML, CSV and source code (TypeScript, Python, Go, Rust, Java, C#…) are inferred automatically from the structure; the JSON Schema is generated in Draft 2020-12.

Source

100% local detection of sensitive patterns: API keys, Bearer tokens, JWTs, AWS/GitHub keys, private keys, passwords, e-mails, phone numbers and card numbers. The anonymized version replaces each value with [REDACTED] while preserving the structure.

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JSON Formatter is 100% free, local and without any size limit (only your browser's memory restricts very large files) — for everyone. Premium unlocks the entire Volade ecosystem.

Beautify, minify & key sortingFree

RFC 8259 validator + smart repairFree

JSONPath RFC 9535, Pointer, diff & convertersFree

Transformation pipeline & encrypted historyPremium

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Features

Much more than a simple beautifier

Architectural privacy guarantee

Parsing, formatting, validating, repairing, querying, diffing and converting all run 100% in the browser. No upload, no remote parsing API, no server storage, no content telemetry. You can cut the network after loading: the tool keeps working.

Privacy policy

Validator, linter & precise repair

The diagnostic shows line, column, offset, JSON path, snippet and expected/encountered token, with a “go to error” button. The linter detects trailing commas, unquoted keys, single quotes, undefined/NaN/Infinity, comments, duplicated keys… then the repair (safe or aggressive) shows exactly what was fixed.

Repair some data

Explore, query & convert

Tree view (colors per type, path copy), table view with sort, filter and CSV/TSV/Markdown export, JSONPath RFC 9535, JSON Pointer, structural diff and converters to YAML, XML, TypeScript, Python, Go, Rust, Java, C#, SQL and JSON Schema. One document, several perspectives.

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How it works

From raw data to a usable result in three steps

Paste, drop or load

Paste an API response, drop a .json, .jsonc, .ndjson or .har file, or pick an example. The import is instant and strictly local: no file ever goes through a server.

Format, validate, repair

Beautify with 2 to 8 spaces or tabs, minify, alphabetical key sorting (recursive or not), real-time RFC 8259 validation with precise diagnostics, and smart repair with mini-diff.

Explore, compare, convert

Tree, table, JSONPath/JSON Pointer queries, structural diff, conversions to more than 15 formats and statistics. Copy the result or download it: everything stays on your device.

Reference

Supported standards and syntax

Standard	Purpose	Details
RFC 8259	JSON format	Strict validators: UTF-8, numbers, escaped strings, no trailing comma, keys must be double-quoted.
RFC 6901	JSON Pointer	Locates /users/0/profile/email, with ~0 / ~1 escaping. Basis of JSON Patch operations.
RFC 9535	JSONPath	Recursive descent, wildcards, slices, unions and expression filters — Internet standard published in 2024.
JSON Schema	Data contract	Draft 2020-12 generation: types, required, enum, arrays, nested objects and detected formats (e-mail, date, UUID, URL).
NDJSON / JSONL	Logging	One JSON per line, UTF-8, separated by \n — detected and convertible to a JSON array.
JSONC / JSON5	JSON + comments	Recognized by the linter and convertible to strict JSON; never mixed up by the RFC 8259 validator.

FAQ

Frequently asked questions

What does “formatting” a JSON actually do?

Formatting (or “beautifying”) re-indents the document and adds line breaks to make it readable: each nesting level is shifted according to the chosen indentation (2, 3, 4, 8 spaces, tab or custom). The operation never changes the value of the data: re-minifying afterwards reproduces exactly the original document.

Why is my JSON “invalid” when it works on my machine?

Most browsers, Python and Node.js accept syntax deviations that the RFC 8259 standard forbids: trailing comma in an object, unquoted keys, single quotes, undefined/NaN/Infinity values, // or /* */ comments, or TRUE/FALSE/NULL constants in capitals. Our Repair tab converts these variants to strict JSON, with the exact list of corrections.

Can formatting overwrite my data?

No. Formatting and sorting work on a copy: after any operation, an integrity check compares the re-parsed result with the original document. On failure, the box shows “Operation failed” and never touches your source — the input always stays intact (immutable Entry → Transformation → Output architecture).

Are my JSON sent anywhere?

Never. Parsing, formatting, validation, repair, queries, diff, conversions and statistics happen in your browser. No remote parsing API, no server storage, no content telemetry. The page only contacts the Volade configuration APIs (Premium buttons, currency), never your data. You can check in the browser network tab: nothing other than the page itself is loaded.

What is JSONPath and what is it useful for?

JSONPath is a query language to extract subsets of a JSON document, now standardized by RFC 9535. For example $.users[?(@.age > 18)].name returns all the names of adult users; $..price collects all prices at any depth. It is the JSON equivalent of XPath for XML — essential to query API responses without writing loops.

Can very large files be formatted?

Yes, within the limits of your browser's memory (typically tens to hundreds of MB). There is no artificial upload limit — it simply doesn't exist since there is no upload. The tree is rendered lazily and heavy operations run through background workers so the interface never blocks.

Difference between JSON and JSONC / JSON5 / NDJSON?

JSONC adds comments; JSON5 additionally adds unquoted keys, single quotes and special values; NDJSON (or JSONL) contains one valid JSON object per line, separated by line breaks — very common for logs and data batches. The linter recognizes these variants and the Convert tab turns them into strict JSON if needed.

What is the Table view for?

When your JSON is a list of homogeneous objects (e.g. a paginated API response), the Table view automatically transposes it into a spreadsheet-style table: dynamic columns, column sorting, search, filtering, then CSV, TSV or Markdown export for Excel, Google Sheets or Notion.

Does formatting change the order of the keys?

Beautify alone preserves the exact order of the keys as they appear. Alphabetical sorting (A → Z or Z → A), recursive or limited to the current level, is a deliberate operation: it is recommended to produce reproducible diffs and deterministic comparisons, for example before computing a hash.

How do I create a JSON Schema from my data?

Convert tab → “JSON Schema”. The tool generates a Draft 2020-12 schema by inferring types, required fields, nested arrays and objects, enums (when few distinct values) and detected formats (e-mail, date, UUID, URL). Perfect to constrain or document an API — all without sending any data.

Online JSON Formatter: the 100% local JSON workbench

Volade JSON Formatter turns your browser into a complete JSON workshop, free and without registration: beautify, minify, strict RFC 8259 validation, smart repair, tree and table views, JSONPath queries, JSON Pointer, structural diff, statistics and dozens of conversions. No data leaves your device: no upload, no account, no content telemetry. Ideal for developers, data analysts, system administrators and anyone who works with raw data.

The page runs entirely in your browser: parsing, formatting, repair, queries and conversions are executed locally, which guarantees total privacy — even for corporate documents, API responses containing personal data or sensitive configuration files. Check for yourself in the browser network tab: no data is ever transmitted.

Beautify and minify RFC 8259-compliant JSON

The Beautify button re-indents your document with the indentation of your choice — 2, 3, 4 or 8 spaces, tab or custom — and the Minify button compresses it to save bandwidth. A strict integrity check guarantees that no transformation alters your data: the re-parsed result is compared with the original document. Alphabetical key sorting, recursive or limited to the current level, produces reproducible diffs and deterministic comparisons.

Validate and repair: linter, precise diagnostics, remediator

The real-time validator compliant with RFC 8259 locates each error precisely: line, column, offset, JSON path, expected and encountered token, with a “go to error” button. The linter detects the deviations that tolerant parsers wrongly accept: trailing commas, unquoted keys, single quotes, undefined / NaN / Infinity values, // or /* */ comments, TRUE / FALSE / NULL constants in capitals and duplicated keys.

The smart repair — safe and aggressive modes — rebuilds damaged documents (truncated JSON, apostrophes instead of quotes, missing commas or braces) and shows exactly the corrections applied thanks to a mini-diff. The ideal tool to recover an API export, a corrupted log file or an answer pasted from a console.

Explore, query and compare

The tree view colors the types (strings, numbers, booleans, null) and copies a JSON path or a JSON Pointer with one click. The table view transposes a list of homogeneous objects into a sortable and filterable data table, exportable in CSV, TSV or Markdown for Excel, Google Sheets or Notion. JSONPath (RFC 9535) queries — including filters like $.users[?(@.age > 18)].name — and JSON Pointer (RFC 6901) extract any subtree; the structural diff compares two documents and lists additions, deletions and modifications with their before/after values.

Convert across the whole data ecosystem

The converter produces JSON to YAML, XML, CSV, TSV, Markdown, TypeScript, JavaScript, Python, Go, Rust, Java, C#, Base64, NDJSON and SQL INSERT, and automatically recognizes close variants (JSONC, JSON5, NDJSON) to normalize them into strict JSON. The JSON Schema Draft 2020-12 generation infers types, required fields, enums and detected formats (e-mail, date, UUID, URL) directly from your data.

Statistics, secret detection and professional use

The statistics panel measures the size in UTF-8 bytes, the depth, the number of nodes, the type distribution and an overall quality score — useful to audit large API responses. Secret detection spots Bearer tokens, API keys and plain-text passwords and offers an anonymized version for safe sharing. File loading, one-click copy and various exports complete this toolbox for daily processing of raw or malformed JSON data.

To go further, discover our other Volade web tools like the UUID generator, the word counter, the color palette generator or the Lorem Ipsum generator — all 100% local, free and in English.

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