Question 1

Does minifying rename my variables?

Accepted Answer

Yes — minify mode mangles (shortens) local variable and function names in addition to removing whitespace and comments, which is standard practice for production JavaScript and produces meaningfully smaller output than whitespace removal alone.

Question 2

Will minifying change how my code behaves?

Accepted Answer

It shouldn't — the minifier only renames local identifiers and removes dead code/whitespace, both of which preserve behavior. Global names, string contents, and public API surfaces are left untouched.

Question 3

Why does it say my code has a syntax error?

Accepted Answer

The minifier parses your JavaScript into an AST before transforming it, so any syntax error (a missing bracket, an invalid token) is caught and reported with a description, rather than silently producing broken output.

Question 4

Is my code sent anywhere?

Accepted Answer

No — both minifying and beautifying run entirely in your browser. Nothing you paste is uploaded.

JS Formatter

Frequently asked questions