Free Online JSON Tools
JSON is the default language of APIs, config files and log pipelines, which means most developers spend part of every day squinting at it. These free JSON tools cover the jobs that come up again and again: pretty-printing a minified API response so you can actually read it, finding the exact line and column where a payload breaks, and turning JSON into the format the next person needs.
Use the JSON Formatter to indent or minify, and the JSON Validator when you need a plain-English explanation of a syntax error such as a trailing comma or single-quoted key. When the data has to leave the developer world, JSON to Excel produces a real .xlsx file for colleagues who live in spreadsheets, while the CSV ↔ JSON and JSON ↔ YAML converters handle imports, exports, Kubernetes manifests and Docker Compose files in both directions.
Every tool parses your data locally in the browser. Nothing is uploaded or logged, so it is safe to paste API responses that contain tokens, customer records or internal configuration. There is no account, no file-size paywall and nothing to install.
All JSON Tools (5)
JSON Formatter
Beautify, pretty print and minify JSON.
Open tool →JSON Validator
Validate and lint JSON syntax, pinpoint errors.
Open tool →JSON to Excel
Convert JSON to a downloadable .xlsx file.
Open tool →CSV ↔ JSON
Convert between CSV and JSON.
Open tool →JSON ↔ YAML
Convert between JSON and YAML.
Open tool →Frequently Asked Questions
What JSON tools does NJHTools offer?↓
Five free tools: a JSON Formatter (beautify and minify), a JSON Validator with line and column error reporting, a JSON to Excel converter that downloads .xlsx files, a two-way CSV ↔ JSON converter, and a two-way JSON ↔ YAML converter.
Is it safe to paste sensitive JSON into these tools?↓
Yes. All parsing, formatting and conversion runs as JavaScript in your own browser. Your JSON is never sent to a server, stored or logged.
What is the difference between the JSON Formatter and the JSON Validator?↓
Both check syntax. The Formatter focuses on reformatting valid JSON (indentation, minifying), while the Validator focuses on diagnosing invalid JSON — it shows the exact line and column of the error, the offending line, and a hint such as a missing or trailing comma.
Can I convert JSON to Excel or CSV for free?↓
Yes. JSON to Excel turns an array of objects (or a single object) into a downloadable .xlsx spreadsheet, and the CSV ↔ JSON converter produces CSV you can open in any spreadsheet app. Both are free with no row limits imposed by the site.
Do I need to install anything?↓
No. The tools work in any modern browser on desktop or mobile with no extension, download or signup.
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