Text / Code Diff
Compare text and source code line by line with readable additions, removals and unchanged context.
Left / original
Right / changed
Compare plain text or source code as inert strings. LF and CRLF are treated alike.
Textual changes, line by line.
The left side is the original, the right side the changed text. A changed line appears as a removal and an addition. Unified output includes line numbers and explicit Added, Removed and Context labels. Code, Markdown, logs and configuration are never executed or rendered as HTML. For structural object comparison, use JSON Diff.
Comparison rules.
LF and CRLF line endings compare equally. A missing final newline remains significant and is labeled. Ignore spaces and tabs removes only ASCII spaces and tabs when comparing; it does not remove line breaks. Ignore case applies JavaScript Unicode lowercase conversion, not locale-sensitive collation. Context rows display the original left text even when ignore options consider it equivalent to the right.
Predictable limits.
Each side accepts 64 KiB UTF-8 and 2,000 lines. Unpaired Unicode surrogates are rejected. The Myers algorithm in jsdiff stops at an edit distance of 1,024 lines; a local worker is also terminated after 2 seconds of computation, with a 5-second startup deadline. Compare smaller sections when a limit is reached.
Output previews show at most 400 rows, 64 KiB of characters and 1,024 characters per line; truncation is explicit. Summary counts cover the computed comparison even if later rows are omitted. Unified view works on mobile without forcing two result columns. Word and character modes are not included.
Local memory only.
Neither text nor differences are uploaded, logged or saved. Edits cancel active work and invalidate results. Reset, page navigation and closing the workspace clear local state.