Strip whitespace from JSON and see the bytes saved. Nothing is uploaded.
The JSON Minifier removes only inter-token whitespace, which RFC 8259 defines as meaningless — on a 26-document sample corpus it saved a median 27.1% of bytes, entirely in the browser.
A JSON minifier strips every space, tab and line break that JSON does not need, producing the smallest equivalent document. Use it before embedding JSON in a query string, a log line, an environment variable or an HTTP request body.
Paste JSON and press Minify. The text is parsed with your browser's JSON.parse, then re-serialized without whitespace. The status bar shows input size, output size and the percentage saved. Pretty-print reverses it with two-space indentation.
No. This page never sends your input to a server — formatting, decoding and hashing all run in this tab, on this device.How that works.
No. Only insignificant whitespace between tokens is removed. Strings, numbers, key order and structure stay exactly the same, so the minified document parses to the same value.
It depends on how it was formatted. Pretty-printed JSON with deep nesting often shrinks 20 to 40 percent; already-compact JSON barely changes.
The input must be valid JSON first. The error message points at the line and column of the first problem — commonly a trailing comma, a comment, or single quotes instead of double quotes.
No. Minifying removes whitespace but the result is still plain JSON any parser can read. Gzip is binary compression applied on top — servers usually do that automatically.
Browse alljson toolsor thefull tool directory.