TxtDiffMerge — Online Text Compare & 3-Way Merge Tool TxtDiffMerge is a free browser-based tool for comparing and merging text. Load two documents to see a side-by-side diff with line-level and character-level highlighting, or load a common ancestor as well to run a 3-way merge and resolve conflicts one chunk at a time.

Side-by-side 2-way text comparison

3-way merge with per-chunk apply and discard controls

Synchronized scrolling, minimap and change-to-change navigation

Ignore whitespace and ignore case comparison options

Inline editing of the merge result with undo and redo

Everything runs in your browser — no file is ever uploaded

JavaScript must be enabled to use the tool.