How to Compare Two Texts Online and Read the Differences

How to Read the Result

• Green marks text that was added and red marks text that was removed. In the Inline view, removed text is also struck through.
• Above the result, the tool counts how many characters were added and removed, which gives a quick sense of how big the change is.
• The comparison is character-level, then small changes are grouped into readable chunks, so a changed word usually shows as one removal and one addition.
• In Side-by-Side view, the left panel shows removals and the right panel shows additions. The panels are not aligned line by line and have no line numbers, so for long files the Inline view is often easier to scan.

Differences That Are Easy to Miss

• Spaces and tabs: every character counts, so replacing a tab with spaces, or adding a space at the end of a line, shows up as a change even though it looks the same.
• Capital letters: "Total" and "total" are different. There is no option to ignore case.
• Line endings: browsers convert Windows line endings to plain line feeds in text boxes, so two texts that differ only in line endings look identical here.
• Pasted formatting: bold, fonts, tracked changes and comments from Word or Google Docs are not compared, only the plain text.

Comparing JSON or Code

Two JSON files with the same data can look completely different if one is minified and the other is indented. Format both the same way first with the JSON/CSV Formatter, then compare them, so only real changes are highlighted. For code in a Git repository, git diff is usually the better tool because it understands files and history.

Other Ways to Compare Text

• Git: git diff --no-index compares any two files, even outside a repository, and --word-diff marks changes inside a line:

git diff --no-index old.txt new.txt
git diff --no-index --word-diff old.txt new.txt

For two files that differ only by "beta" becoming "beta 2", the word diff prints:

alpha
beta {+2+}
gamma

• Command line: diff on macOS and Linux, and fc on Windows, compare two files and print the differences.
• Microsoft Word: the Compare command on the Review tab compares two documents and shows the differences as revision marks.

Conclusion

For quick checks of pasted text or code, a browser diff tool is the fastest option. Format structured data the same way before you compare it, remember that every space and capital letter counts, and use git diff when you need line endings compared, or Word's Compare command for Word documents.