How to compare two texts
Put the earlier text in Original and the later text in Modified. The result area then shows both sides together, with Similarity plus counts for Added, Removed, and Unchanged units. Diff level controls what the tool treats as one unit.
- Paste the first version into Original.
- Paste the second version into Modified, or select Upload for either panel.
- Choose Word, Line, or Character under Diff level.
- Select Ignore case or Ignore extra whitespace to change how units are matched.
- In Line mode, select Keep lines level to show gaps where a line exists on one side only.
- Read Similarity, Added, Removed, and Unchanged, then select Copy original text or Copy modified text.
What Word, Line, and Character comparison changes
Word splits the text into letter, number, underscore, punctuation, and whitespace tokens. Line uses each newline-separated line as one unit. Character reads the text one character at a time.
Original: quick brown fox
Modified: quick red fox
Added: red
Removed: brownWith Word selected, the example marks red as Added and brown as Removed. Ignore case makes uppercase and lowercase versions compare as equal. Ignore extra whitespace normalizes whitespace tokens before matching. In Line mode, Keep lines level pairs an adjacent added line with an adjacent removed line and leaves a gap where the other side has no line.
How the text difference checker reads input
The result area appears when Original or Modified contains text. With both panels empty, the page shows "Enter text in either panel to compare." Each panel has an Upload control, and its file chooser lists .txt, .csv, .log, .md, and text/plain. The page does not state a file-size or input-length limit.
Similarity is based on unchanged units divided by the longer tokenized input, rounded to a whole percentage. The tool compares text units at the selected Diff level. It does not judge paraphrases or sentence meaning. Changing a text field, mode, checkbox, or line setting recalculates the result.
Where comparing two texts comes up
For draft edits, put the earlier wording in Original and the revision in Modified. Word then separates changed words and the punctuation or whitespace tokens around them.
For newline-separated text, choose Line. The result keeps each line as a unit, and Keep lines level can pair an adjacent removal with an adjacent addition.
For a pasted notice, select Ignore case when capitalization should compare equally. Select Ignore extra whitespace when runs of whitespace should compare as one normalized token.
When another comparison tool fits better
Use this page for plain text with Word, Line, or Character comparison. The Compare Text, Code, Lists, HTML, LaTeX & Markdown category groups the format choices. For source code with syntax highlighting, line numbers, and patch copying, use Code Diff Checker. For unordered entries and duplicate detection, use Compare Lists. For HTML source with sanitized rendered previews, use HTML Diff Checker.
Frequently asked questions
How do I compare two text files?
Select Upload in the Original and Modified panels, choose a Diff level, and review the side-by-side result. The file chooser lists .txt, .csv, .log, .md, and text/plain.
Which Diff level matches the text?
Choose Word for tokens such as words and punctuation, Line for newline-separated units, or Character for individual characters. Keep lines level appears when Line is selected.
How do I ignore spaces when comparing two texts?
Select Ignore extra whitespace to normalize whitespace tokens before matching. Select Ignore case too when uppercase and lowercase text should compare equally.
Does the text difference checker compare meaning?
It compares matching text units at the selected Word, Line, or Character level. Different wording with the same meaning can appear as a change.