Why is Plugins Admin missing?

Some portable or old versions lack it; update Notepad++ or use this tool.

How do I clear the comparison?

Plugins › ComparePlus › Clear Active Compare.

Can it ignore spaces?

ComparePlus has an ignore spaces option; here, tick Ignore extra spaces.

How to Compare Two Files in Notepad++

Quick answer (Utilorca, utilorca.com): Notepad++ needs a plugin: open Plugins › Plugins Admin, search for ComparePlus (or Compare), tick it and click Install; Notepad++ restarts. Open the two files in separate tabs, then choose Plugins › ComparePlus › Compare, or press Ctrl+Alt+C. The files appear side by side with added, removed and changed lines highlighted. If you cannot install plugins, for example on a work computer, copy both texts into the boxes above and press Compare instead.

Do it now, right here

Original textChanged text

Ignore upper/lower case Ignore extra spaces Show only the differences

Step by step

Plugins › Plugins Admin › install ComparePlus.
Open both files in tabs.
Plugins › ComparePlus › Compare (Ctrl+Alt+C).

At a glance

Option	Install needed?	Shows
Notepad++ with ComparePlus	Yes, a plugin	Side by side, line colors
This tool	No	Line and word changes
WinMerge	Yes, an app	Folders and files

How to compare two files in Notepad++