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JSON Minifier

Strip whitespace from JSON to produce the smallest valid payload for APIs and storage.

Runs 100% in your browser — nothing is uploaded

About this tool

The JSON Minifier removes all non-essential whitespace — spaces, newlines, and indentation — from a JSON document, producing the most compact valid representation. This is the operation compilers and bundlers perform before shipping JSON to production: smaller payloads mean faster network transfers, lower storage costs, and less bandwidth consumed by mobile clients.

Minification is purely structural: every key, value, and nested object or array is preserved exactly. Only cosmetic whitespace is removed. The output is valid JSON and can be passed directly to any JSON parser. The original input is never modified.

All processing happens in your browser using a built-in JavaScript JSON parse/stringify cycle. Nothing leaves your tab. Use the Paste Sample button to see a before-and-after example, and the Copy button to grab the output for pasting into your code or terminal. Byte counts before and after are shown so you can see the savings at a glance.

Frequently asked questions

Is minified JSON still valid?
Yes. Whitespace (spaces, tabs, newlines) is not semantically meaningful in JSON. Any JSON parser will read minified JSON identically to the formatted version.
Does this tool validate the JSON before minifying?
Yes. It parses the input first using the browser's built-in JSON.parse. If your JSON is invalid, it will show an error rather than silently producing malformed output.
How much smaller will my JSON be?
Savings depend on how much whitespace the original has. Heavily indented, multi-line JSON may shrink by 30–60%. Already-compact JSON may barely change.
Can I pipe the output back into the formatter?
Yes — copy the minified output and paste it into the JSON Formatter to expand it again. You can round-trip between the two tools freely.

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