File Compare (Diff)

Side by side, with aligned lines

Both panes always show the same number of lines: where one side has something the other lacks, a visual gap is inserted — so matching parts stay at the same height and comparing becomes reading, not hunting. Removed lines show in red, added in green and modified in amber, with the exact changed fragment marked inside the line.

On the side, a minimap shows where every difference sits in the whole file — click anywhere on it to jump straight there, just like the good desktop comparers.

Merge: resolve differences without leaving the screen

Every difference block has arrows to copy that chunk to the left or to the right. Resolve block by block (with undo if you change your mind) until the tool reports both sides are identical. You can also copy everything to one side at once, or swap sides.

Real comparison options

Ignore case, whitespace (leading/trailing or all of it) and blank lines — essential when comparing reformatted code, system exports or configs that only changed indentation. Ignored differences show dimmed and stay out of the count.

Export the result or the patch

Download either side as a file, copy it to the clipboard, or generate a unified diff (.patch) — the same format used by version control tools, ready to attach to a ticket or review with your team.

Works where desktop tools can't

Because it runs in the browser, it works on any system — Windows, Mac, Linux and even your phone, where the unified view (single column, code-review style) keeps reading comfortable. And since processing is local, your files never leave your device: nothing is uploaded.

How to use

Paste text or drop a file on each side and click "Compare". Use the toolbar arrows (or Alt+↑/Alt+↓) to move between differences, and the small arrows between the panes to copy a block to the other side. Adjust the comparison options if you need to ignore whitespace or case. When done, export whichever side you want, or the patch with the changes.