JSON Minifier

What this does

So you have tidied up your JSON, it looks lovely with all its indentation, and now you need to ship it. For machines, all that nice spacing is dead weight. This strips it out. Paste your JSON, hit Minify, and you get the same data squeezed onto a single line, ready to drop into an API call or a config file.

How to use it

1. Paste your JSON into the box.
2. Hit Minify.
3. Grab the compact result with the Copy button.

How it works

The tool reads your JSON with the browser's built-in parser and writes it straight back out with no spaces and no line breaks. Where a formatter adds indentation, this does the reverse and removes every bit of spacing that the JSON grammar does not need. It happens right here on the page, so nothing you paste is sent anywhere.

Why minify JSON

Why bother? Because size adds up. Whitespace makes JSON pleasant for a person to read, but a server or browser does not care about pretty, it just has to move the bytes. On a large response, or one that gets sent thousands of times a day, all those spaces and newlines turn into real bandwidth and storage.

The good news is that this is completely safe to do. In JSON, the spacing between values carries no meaning, so removing it does not change your data one bit. A program reading the minified version gets exactly the same result as it would from the spaced-out one.

What you give up is readability, so the usual habit is simple. Keep a formatted copy for when you are editing or debugging, and minify only when you are about to send or store it. If you need to read a minified blob later, you can always run it back through a formatter.

A quick example

Here is a small object with the spacing a person would write:

{
    "id": 7,
    "tags": ["new", "sale"],
    "inStock": true
}

And the same thing minified:

{"id":7,"tags":["new","sale"],"inStock":true}

Identical data, fewer bytes.

Questions people ask

References

1. Internet Engineering Task Force. RFC 8259: The JavaScript Object Notation (JSON) Data Interchange Format. https://www.rfc-editor.org/rfc/rfc8259
2. MDN Web Docs. JSON.stringify(). https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/JSON/stringify