JSON Minifier
Minify JSON to a single compact line, validating it along the way.
Pretty-printed JSON is for reading; production payloads, config strings and environment variables usually want the compact form. Minifying by hand deleting whitespace invites broken strings; minifying with a proper parser is instant and — as a side effect — validates the JSON.
Paste any JSON and get the minified single-line version, or a precise error message if the input isn't valid JSON. Formatting-only whitespace is removed; whitespace inside string values is naturally preserved.
How to use JSON Minifier
- 1
Paste your JSON
Pretty-printed or messy — any valid JSON.
- 2
Copy the compact output
One line, no formatting whitespace.
- 3
Fix any reported errors
Invalid JSON shows the parser's error message.
Features
- Parses and re-serializes — guarantees valid output
- Doubles as a JSON validator
- Shows byte-size savings
Frequently asked questions
Common mistakes to avoid
- Minifying JSON5 or JSONC (comments, trailing commas) — standard JSON parsers reject those extensions.
- Storing minified JSON as the editable source — keep the readable version for humans.
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