Apply Git Diff/Patch Online · Hunk Highlighting & Tolerant Mode

Two side-by-side editors: Code (left) and Patch/Diff (right).
Quick actions: Copy, Paste, Paste into code, and Manual snapshot.
“Apply patch” button with hunk counter and processing time.
Always-visible, collapsible “Output / errors” pane below the patch editor.
Editor background tint by result: green (OK), yellow (partial), red (error).
Zebra striping per hunk in the patch editor for easier reading.
Status pills (OK/Partial/Error) and hunk count; click to jump to the next failure.
Tab bar with editable names (double‑click/double‑tap) and unsaved‑changes indicator.

Supports standard unified diffs and headerless patches; recognizes implicit “@@” hunks.
Whitespace‑tolerant: edge trim, exact, ignore indentation, ignore all whitespace, and a loose mode that ignores quotes/escapes/comments.
Respects and normalizes line endings (LF/CRLF) and preserves the final newline if it existed.
Context insertions when there are no deletions; local scan when ctx/del/add are mixed.
Avoids duplicate insertions if the content is already applied (idempotent).
Recognizes and preserves “No newline at end of file” and common Git headers, ignoring them while applying.
Auto‑names the tab from ---/+++ diff headers when appropriate.

Highlights problematic lines in the code and marks the line number with a dot.
Marks the corresponding line in the patch editor for cross‑reference.
Detailed attempt log (mode used, candidates, failure reason, expected vs. actual).
Failure navigation with Alt+↑ and Alt+↓.

Per‑tab history with automatic snapshots after applying a patch and on‑demand manual snapshots.
Automatic snapshot when pasting or dragging content into the code editor.
“Original” option to return to the tab’s initial state.
Each entry shows date/time, hunks applied, and size (lines/bytes).

Download the active file as .txt respecting the tab name.
Download the entire project as a ZIP (one file per tab).
Drag and drop files or text into either editor.
If you drop a file into the code editor, its content is used and the tab may be renamed after it.
If you paste/drag a diff into the patch editor, the file is detected and the tab can be named automatically.

Quickly copy the code editor’s content.
Paste from the clipboard into both editors.
Automatic copy of the result to the clipboard when the patch applies 100% (status: “Applied, copied to clipboard”).

Interface available in 13 languages (es, en, fr, de, it, pt, ru, zh, ja, ko, ar, hi, tr).
Language selector with “Auto” mode; persisted in the browser.
The URL includes ?lang=XX to share the language.
Right‑to‑left writing support for Arabic.

Projects and history are stored locally in your browser (IndexedDB).
Clipboard is used locally; your browser may ask for permission.
Language packs are loaded from "/i18n/<code>.json" without uploading your files.