Text Differ
Format & CompareCompare two blocks of text line by line
Original Text
Modified Text
About the Text Differ
A side-by-side text differ for comparing two versions of code, config, or prose. Paste the original and modified text, run the comparison, and see exactly which lines were added or removed — useful for reviewing changes without opening a full diff tool or version control client.
It's a fast way to check what actually changed between two pastes of text — two drafts of a document, a config file before and after an edit, or output from two runs of the same command — without spinning up a local git repo or a full IDE just to compare them.
How to Use the Text Differ
Paste the original text on the left and the modified text on the right.
Run the comparison and review additions (green) and deletions (red) side by side.
Copy or export the result as needed for your review or documentation.
Frequently Asked Questions
What diff algorithm does this use?
A line-based longest common subsequence (LCS) comparison, the same family of algorithm behind most code diff tools. It runs entirely in JavaScript in your browser.
Does it compare characters or whole lines?
Lines. Each line in the original is matched against the modified text, and unmatched lines are shown as additions (green) or deletions (red) side by side.
Is there a size limit?
Very large documents fall back to a faster positional comparison instead of the full LCS table, so the tab stays responsive rather than freezing on huge inputs.
Can I use this to compare two versions of source code?
Yes — it works on any plain text, including source code. It won't understand a language's syntax the way a code-review tool does, but for spotting exactly which lines changed between two pastes, a line-based diff is exactly the right tool.