Does it work offline?

Yes. Once the page has loaded, everything runs locally in your browser — no network calls, no server round-trips.

Is my data sent anywhere?

No. All parsing, formatting, and diffing happens entirely in your browser. Your JSON never leaves your device.

What's the maximum size it can handle?

Your browser's memory is the only limit. Files up to a few megabytes feel instant; larger payloads may take a moment to parse.

Does it accept JSON5 or JSONC (with comments)?

It auto-repairs common issues like trailing commas and single-quoted strings. Pure comment-only syntax (// …) is not supported — strip those before pasting.

Can I format a JSON file from my computer?

Yes — drag and drop any .json file straight onto the editor, or click the ⋮ menu and choose Load file. The file is read locally; nothing is uploaded.

How does the Diff mode work?

Paste one JSON payload into the Left pane and another into the Right pane. The Diff output below highlights added lines in green and removed lines in red. It compares the formatted JSON semantically — key order doesn't affect the result.

Can I convert JSON to YAML, CSV, or TypeScript?

Yes — snaptxt has dedicated free tools for each: use the YAML ↔ JSON Converter for YAML, the CSV to JSON Converter for CSV, and the JSON to TypeScript tool to generate TypeScript interfaces automatically from any JSON payload.

How does this compare to jsonformatter.org?

jsonformatter.org sends your JSON to their servers for processing. snaptxt.app runs entirely in your browser — nothing is ever uploaded — and adds a side-by-side semantic diff view, collapsible tree explorer, and shareable links, all without creating an account.

How does this compare to JSONLint?

JSONLint validates JSON and highlights errors, but that's where it stops. snaptxt's JSON Formatter also pretty-prints, minifies, diffs two payloads, and lets you explore the structure as a collapsible tree — all without uploading your data.

JSON Formatter and Validator

Free online JSON formatter, validator, and beautifier — pretty-print, minify, diff, and explore JSON. Nothing ever uploaded.

Input

Formatted

How to use it

1Paste or drag-and-drop your JSON into the editor. It auto-formats valid JSON on paste so you see clean output straight away.
2Pick a mode: Format (pretty-print with 2-space, 4-space, or tab indent), Minify (compact single line), Tree (collapsible key explorer), or Diff (side-by-side comparison).
3Use the toolbar to Search inside the JSON, Download the result as a .json file, or Copy it to your clipboard.
4If your JSON has a typo, the inline linter highlights the exact line and column so you can fix it fast.

Common use cases

Debug API responses and spot malformed, missing, or unexpected fields at a glance.
Minify a payload to embed inside a query parameter, environment variable, or test fixture.
Compare a before-and-after API response with the Diff view to see exactly what changed.
Browse a deeply nested config file without losing your place using the collapsible Tree explorer.
Share a formatted snippet with a colleague via the Share link — no account or login needed.

Frequently asked questions

Does it work offline?: Yes. Once the page has loaded, everything runs locally in your browser — no network calls, no server round-trips.
Is my data sent anywhere?: No. All parsing, formatting, and diffing happens entirely in your browser. Your JSON never leaves your device.
What's the maximum size it can handle?: Your browser's memory is the only limit. Files up to a few megabytes feel instant; larger payloads may take a moment to parse.
Does it accept JSON5 or JSONC (with comments)?: It auto-repairs common issues like trailing commas and single-quoted strings. Pure comment-only syntax (// …) is not supported — strip those before pasting.
Can I format a JSON file from my computer?: Yes — drag and drop any .json file straight onto the editor, or click the ⋮ menu and choose Load file. The file is read locally; nothing is uploaded.
How does the Diff mode work?: Paste one JSON payload into the Left pane and another into the Right pane. The Diff output below highlights added lines in green and removed lines in red. It compares the formatted JSON semantically — key order doesn't affect the result.
Can I convert JSON to YAML, CSV, or TypeScript?: Yes — snaptxt has dedicated free tools for each: use the YAML ↔ JSON Converter for YAML, the CSV to JSON Converter for CSV, and the JSON to TypeScript tool to generate TypeScript interfaces automatically from any JSON payload.
How does this compare to jsonformatter.org?: jsonformatter.org sends your JSON to their servers for processing. snaptxt.app runs entirely in your browser — nothing is ever uploaded — and adds a side-by-side semantic diff view, collapsible tree explorer, and shareable links, all without creating an account.
How does this compare to JSONLint?: JSONLint validates JSON and highlights errors, but that's where it stops. snaptxt's JSON Formatter also pretty-prints, minifies, diffs two payloads, and lets you explore the structure as a collapsible tree — all without uploading your data.

Try next

JSON to TypeScript

Generate TypeScript interfaces or type aliases from JSON.

YAML ↔ JSON Converter

Bidirectional YAML / JSON conversion with multi-document support and indentation control. Free, in your browser.

Convert CSV to JSON

Bidirectional CSV / TSV / JSON conversion. Custom delimiters, header detection, auto-typed numbers. Free, in your browser.