How to Compare Two Files in Notepad++

Notepad++ doesn't compare files out of the box - the feature lives in a separate, official plugin called Compare that most users have to install manually the first time they need it. Here's exactly how to get it running and read its output, plus what to do when it doesn't quite fit the job.

Quick answer

Install the Compare plugin via Plugins > Plugins Admin, search 'Compare', check it, click Install, and restart Notepad++. Then open both files as tabs and run Plugins > Compare > Compare. Differing lines are highlighted in one color per file, side by side. Notepad++ is Windows-only and some versions don't show word-level highlighting within a changed line - for those cases, or on Mac/Linux, a browser-based diff tool is a faster no-install alternative.

Installing the Compare plugin

Open Plugins > Plugins Admin from the Notepad++ menu bar. In the search field, type Compare. Check the box next to the plugin (published by the Notepad++ Compare project), click Install, and allow Notepad++ to restart when it asks. Once it restarts, you'll see a new Compare entry under the Plugins menu - this install is one-time, it stays available in every future session.

Running a comparison

Open both files you want to compare as separate tabs in Notepad++ - use File > Open for each, or drag both files into the window at once. Click into either tab so it's active, then go to Plugins > Compare > Compare. Notepad++ arranges both files side by side in a split view and scrolls them in sync as you move through either one.

Reading the color coding

Lines that exist only in the first file get one highlight color, lines only in the second file get a different one, and lines present in both but edited typically get a third, distinct highlight. The exact shades depend on your Notepad++ theme and plugin version - if the defaults are hard to read, check Plugins > Compare for a settings or color-customization option.

Limitations worth knowing before you rely on it

Some versions of the Compare plugin highlight an entire line as changed without showing which characters within that line actually differ, which makes a single-character difference on a long line easy to miss visually. Notepad++ is also Windows-only - there's no official Mac or Linux build, so this specific workflow isn't available if you're on a different platform, and you'll need a different editor or a browser-based tool instead. It's also a manual, per-session workflow: there's no way to compare two files without first opening both of them as tabs.

The no-install alternative

If you just need a quick answer - not at your usual machine, on a Mac, comparing pasted text rather than saved files, or want inline word-level highlighting rather than whole-line highlighting - pasting both blocks of text into a browser-based diff tool skips the plugin entirely. It works identically on Windows, Mac, Linux, and mobile, and shows the difference the moment you paste, with nothing to install.

Paste two blocks of text and see the difference instantly.

Open Text Diff →

Want more on comparing text online?

See the full guide to comparing text online, including download options.

Read the guide →

Frequently Asked Questions

Does Notepad++ compare files out of the box?

No - file comparison in Notepad++ requires the Compare plugin, which isn't installed by default. Install it once through the built-in Plugins Admin (Plugins > Plugins Admin, search "Compare", check the box, click Install) and it stays available for every future comparison.

How do I install the Compare plugin in Notepad++?

Open Plugins > Plugins Admin from the menu bar. In the search box, type Compare. Check the box next to the plugin named Compare, click Install, and let Notepad++ restart when prompted. After restarting, you'll see a new Compare submenu under Plugins.

How do I compare two files once the plugin is installed?

Open both files as tabs in Notepad++ (File > Open, or drag both files into the window). Click into one of the two tabs, then go to Plugins > Compare > Compare, or Plugins > Compare > Compare to Next / Compare to Previous depending on your version. Notepad++ splits the view side by side and highlights the differences.

What do the colors mean in Notepad++ Compare?

By default, lines only present in one file are highlighted in one color (often a light red or orange background) and lines only in the other file in a different color (often light green). Changed lines - present in both but with edits - typically get a third, distinct highlight. Exact colors depend on your version and theme; check Plugins > Compare > Set as First / Compare Settings to see or adjust them.

Does Notepad++ Compare show word-level differences within a line?

Depends on the version. Some releases of the Compare plugin only highlight entire lines as changed without showing exactly which characters differ within that line, which makes it harder to spot a one-character difference on a long line. If your version doesn't show inline word-level highlighting, a browser-based text diff with inline highlighting can be easier to read for that specific case.

Can I compare two files in Notepad++ on Mac or Linux?

Not directly - Notepad++ is Windows-only (it does not have an official Mac or Linux build). Mac and Linux users looking to do the same line-by-line comparison need either a different editor with a diff feature (VS Code, for example) or a browser-based diff tool, which works identically on any operating system.

What if I just want to paste two blocks of text and see the difference, without opening files?

Installing a plugin is worth it if you compare files in Notepad++ often. For a one-off comparison, or if you're not at your usual computer, pasting both blocks of text directly into a browser-based diff tool skips the plugin install entirely and works on any device, including mobile.