Guide
How to format JSON online (pretty-print & minify)
Format messy API JSON into readable indented output, or minify for transport — privately in your browser with Tools by RS Roshi.
Published 2026-07-23
API responses and config files often arrive as a single dense line. Pretty-printing makes nested objects readable; minifying removes whitespace for smaller payloads.
Pretty-print JSON in the browser
- Open JSON Formatter and paste or upload your payload.
- Run Pretty print (⌘/Ctrl + Enter on most tools).
- Copy or download the indented result.
Validate before you ship
If formatting fails, the document is not valid JSON. Switch to JSON Validator for a parse report with line and column when available, then inspect structure in JSON Viewer.
When to minify
- Preparing compact bodies for HTTP or message queues
- Reducing noise in tickets when reviewers prefer one line
- Pairing with Base64 encoding of a JSON string for opaque fields
Related tools
- JSON Formatter — pretty-print and minify
- JSON Validator — parse checks and size stats
- JSON Viewer — expandable tree with paths
Try these tools
JSON Formatter
Format, beautify, and minify JSON in your browser. Free, private, and instant — no upload to a server.
JSON Validator
Validate JSON instantly in your browser. See type, size, and node counts — or exact parse errors with line and column.
JSON Viewer
Explore JSON as an interactive tree with paths, types, and expandable nodes — all processed locally in your browser.
Frequently asked questions
Is formatting the same as validating?
No. Formatting rewrites whitespace. Validation checks whether the text parses as JSON. Use both when debugging payloads.
Does this upload my JSON?
No. JSON Formatter, Validator, and Viewer on this site run in your browser by default.
More long-form writing may also appear on blog.rsroshi.dev.