Safe minification, and what that costs
This removes comments and whitespace. It does not shorten variable names. Renaming needs full scope analysis, and a renamer that is subtly wrong produces code that works until the one path nobody tested — which is a bad trade for a few more percent.
So expect roughly a third off, not two thirds. If you need the rest, a build step with a proper compiler is the honest answer; this is for the times you want a smaller file now and want to be certain it still runs.
The newline that cannot be removed
JavaScript inserts semicolons at line ends in a few places. return followed by a line break means return nothing, so joining those two lines changes what the function gives back. Those breaks are kept. Comments beginning /*! are kept too, by the usual convention for licence headers.
Frequently asked questions
Is my code uploaded anywhere?
No. Your code is parsed and rewritten inside the tab. Minification happens locally, which is what makes it safe to paste in code that has not shipped yet.
Will the minified version behave the same?
Yes. Nothing is renamed, reordered or rewritten — only comments and whitespace are removed, and the line breaks that carry meaning are left in place.
Why is it not as small as other minifiers?
Because they rename your variables and this does not. That is a deliberate trade: a smaller file is not worth a chance of changed behaviour.
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