Unminify a file

Have a minified script or library you need to understand? Write a readable copy so you can follow its logic in your editor:

npx wakaru input.js -o output.js

This keeps the code in one file. If you want to split a bundle into modules, see Unpack a bundle.

See what changes

Minifiers squeeze conditions and several actions into a single expression:

function submit(e){e.valid&&(track("submit"),send(e.data)),e.pending=!1}

Wakaru turns those actions back into separate statements:

function submit(e) {
    if (e.valid) {
        track("submit");
        send(e.data);
    }
    e.pending = false;
}

You can now see the two paths: valid input triggers tracking and sending, while pending is cleared either way.

For transpiled code, Wakaru also restores modern syntax such as classes and async/await where it recognizes the compiled patterns. See What is Wakaru for an example.

Why are some names still short?

The parameter e stays e in this example. Wakaru improves names when the code provides enough clues, but most names lost during minification cannot be recovered from the code alone.

If you have a source map, use it to recover original names. See Source maps. Without one, a coding agent can help choose names from context once the code is readable. Those names are interpretations, not the original source names.

If you need to run the result

Start with minimal to prioritize preserving the input's behavior:

npx wakaru input.js --level minimal -o output.js

Wakaru aims to produce working code, but cannot guarantee every case. Check the result in your application. Rewrite levels explains the tradeoffs and shows how the output can differ.

For a quick comparison without writing files, try your code in the playground.