Start with the same passage in both versions
Copy the original into the first editor and the revised version into the second. Include enough surrounding text to understand each edit. If you have files, open your two text files instead. You can compare a blank side with a filled side to see an entirely added or removed passage.
Choose a useful level of detail
| Mode | Best for | What you will see |
|---|---|---|
| Word | Drafts, emails and articles | Changed words, spaces and punctuation |
| Character | Typos, numbers and short strings | Individual characters added or removed |
| Line | Lists, logs and source files | Whole lines added or removed |
Read the result in context
Green text with a + is an addition in the revised version. Red text with a − is a removal from the original. A replacement usually appears as a removal followed by an addition. Adjacent changes are grouped together; a change group is not a count of mistakes.
Use side-by-side view to read the versions separately or inline view to see edits together. Previous and next controls take you between change groups. A moved sentence may appear as a deletion and an addition: this tool does not separately detect moves.
Use ignore options carefully
Ignore case treats uppercase and lowercase as equal. Ignore whitespace removes spaces, tabs and line breaks from comparison keys while preserving your original text in the preview. “a b” and “ab” match. Word and line groups can become larger because boundaries are ignored, so use character mode for more detail or keep this option off when spaces matter. Windows and Unix line endings are always treated as equivalent.
Keep a record and make your own final decision
Copy or download the report after comparing. It contains the selected options, change counts, both unmodified inputs and marked comparison text. It is a readable report, not a patch you can apply to a file. Changing the inputs clears the previous result so you cannot accidentally export an outdated comparison.
Text comparison finds literal differences. It cannot tell you whether a revision is accurate, legally equivalent or better written. For publication, use a proofreading checklist alongside the comparison.