Text Diff

About Text Diff

OptiPix Text Diff is a full-featured text comparison tool that instantly shows you what changed between two versions of any text. Paste your Original and Modified text into the two panes and get a detailed diff in milliseconds. Choose between Side-by-Side view — with aligned line numbers, red-highlighted deletions, green additions, and yellow changed lines — or Unified diff view with the classic -/+ prefix format and 3 lines of context around each change. Within changed lines, character-level or word-level inline highlighting pinpoints exactly which characters differ. Options let you ignore case, collapse whitespace differences, and trim trailing spaces so you focus on meaningful changes. A live statistics panel shows lines added, deleted, changed, unchanged, and overall percentage identical. Copy the result as a standard unified diff string or download it as a .diff file. Drop .txt files directly onto either pane to load them. All processing happens 100% in your browser — your text never leaves your device.

How It Works

The tool uses the 'diff' npm library (diffLines, diffWords, diffChars) to compute an edit-distance-based diff between the two inputs. For Side-by-Side view it pairs removed/added line blocks and aligns them; for Unified view it applies a 3-line context window. Inline highlighting runs a second word- or character-level diff pass on each changed line pair.

Use Cases

• •Compare two versions of a document or article
• •Review code changes without a full IDE
• •Spot differences between configuration files
• •Verify that edits were applied correctly in any text
• •Generate a .diff patch file for sharing changes