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JSON tools

JSON Minifier

Strip every non-significant whitespace character from JSON. Output is byte-identical in meaning, smaller in size. Validates first; runs in your browser.

Minified
{"hello":"world","items":[1,2,3]}
Stores the JSON behind a public URL with version history. Free, no sign-up needed.

How it works

We parse with the standard JSON parser and re-serialise without indentation or padding. Whitespace inside string values is preserved (it's significant); all other whitespace is removed. The output parses to the same value as the input.

Frequently asked questions

Does minifying JSON change its meaning?
No. JSON whitespace outside of string values is non-significant per RFC 8259. The minified output parses to the exact same value — same keys, same key order, same types.
How much does minification save?
It depends on the input. Pretty-printed JSON typically shrinks 30–60% on minification. Combined with gzip on the wire, the savings on the network are smaller — but you still save bytes in storage, in logs, and on hot paths where compression isn't applied.
Should I minify before sending JSON over HTTPS?
If your transport layer uses gzip or brotli (most do), the network savings of minification are minimal. Minify when you're storing JSON in a tight space (cookies, query strings, headers, certain database columns) or when bytes literally cost money.
Does it preserve unicode escapes?
Yes. The output uses standard JSON serialisation, which preserves all string content byte-for-byte. Non-ASCII characters remain as themselves; \uXXXX escapes remain escaped.
Is my JSON sent anywhere?
No. Minification runs entirely in your browser. Your JSON only leaves the page if you click "Save & share" to store it as a public blob.

Related tools

Need to host minified JSON behind a stable URL? Save it on superjsonblob — the response wire format is whatever you stored.