Tabs to Spaces Converter

Tabs and spaces are the oldest argument in programming, and most of the time you do not get to pick: the project has a style, the linter enforces it, and a file that arrived from somewhere else has the wrong one. This converter changes the indentation of pasted code from tabs to spaces or from spaces to tabs, at a tab width of 2, 4, or 8.

The conversion treats a tab the way an editor does. A tab moves to the next tab stop rather than expanding into a fixed number of spaces, so a tab sitting in column 3 at a width of 4 becomes two spaces, not four. That is what keeps a converted file looking identical to the original instead of drifting a few columns to the right on every nested line. Going the other way, the indentation is measured first and then rebuilt out of tabs, so a file that mixes both ends up consistent rather than stacking tabs on top of the spaces that were already there.

By default only the leading whitespace on each line is converted. That is the setting you want almost always, because rewriting whitespace across the whole line will also rewrite the spacing inside string literals and any comment that was aligned by hand. The wider option is there when you genuinely want it, with a warning attached. There is also a toggle to strip trailing whitespace, which is the other change most linters ask for. For broader cleanup, see the whitespace remover and the text cleaner, or use the JSON formatter when the file is JSON and you want it reindented properly.