Does minifying validate my JSON?

Yes. The tool parses your input with the browser JSON engine and re-serialises it compactly, so invalid JSON is rejected with the exact parser error rather than producing broken output.

Will it change my data?

No values are altered — only whitespace is removed. Note that JSON object key order and number formatting follow the JSON specification, so the output is semantically identical.

How much smaller will the minified JSON be?

It depends on how heavily indented and spaced the original is. Pretty-printed JSON with two-space indentation often shrinks 20-40%. The tool reports the new character count and the percentage saved.

Does minifying strip comments?

JSON has no comments in the specification, so if your input contains // or /* */ comments it is not valid JSON and will be rejected. Remove comments first, then minify.

Will it preserve number precision?

Numbers are re-serialised through the native JSON engine, which preserves the value within the limits of double-precision floating point. Very large integers beyond that range can lose precision, as they would in any standard JSON parser.

What is the difference between minifying and just deleting spaces?

Naively deleting whitespace can corrupt string values that contain spaces. This tool parses the JSON and re-serialises it, so spaces inside strings are preserved and only insignificant whitespace between tokens is removed.

Is my JSON uploaded anywhere?

No — parsing and minification happen entirely in your browser and nothing is sent to a server.

JSON Minifier — Gera Tools

Minify and validate JSON locally

Pretty-printed JSON is easy to read but wastes bytes in API payloads, config files and storage. This tool strips every bit of insignificant whitespace to produce a single compact line, and because it parses the input first you get validation in the same step — invalid JSON shows the exact parser error instead of silently producing broken output.

How it works

The minifier runs JSON.parse on your input to build the data structure, then JSON.stringify with no indentation argument to serialise it back as compactly as possible. Because it works on the parsed data rather than the raw text:

spaces and newlines inside string values are preserved;
only insignificant whitespace between tokens is removed;
anything that is not valid JSON is rejected with the parser’s error message.

After minifying, the tool reports the new character count and how much you saved.

Example

This pretty-printed input:

{
  "name": "api",
  "tags": [ "a", "b" ]
}

minifies to:

{"name":"api","tags":["a","b"]}

The data is identical; only the indentation and spacing between tokens are gone. It runs entirely in your browser, so sensitive data is never uploaded.