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Text diff

Paste two versions and see what changed. Line mode for code and configuration, word mode for prose.

Additions carry a plus and an underline, removals a minus and a strike, so the two are told apart without depending on colour.

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Paste something into both boxes to see what changed.

Questions

Is what I paste sent anywhere?
No. Every tool in this kit runs in the page itself. There is no server here that receives what you paste, and you can check it in your browser's network tab: using a tool produces no request carrying your input at all.
When should I use word mode instead of line mode?
For prose. A line diff reports a whole paragraph as changed because one word in the middle of it moved, which tells you nothing. Word mode finds the word.
Does a trailing newline count as a difference?
No. Both sides are normalised to end the same way before comparing, because one file ending in a newline and another not is a difference nobody means and every editor produces. Windows line endings are normalised too, so a CRLF file against an LF one is not reported as entirely different.
Is whitespace inside a line ignored?
No. Two lines differing only by indentation are a real difference, and in a language where indentation is syntax it is the whole difference.

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