A proofreader's desk — compare two versions (plain text, code, or Word .docx), or 🔍 inspect one for hidden and suspicious characters. Free, no upload, no account.
🔒 Your text and files never leave your device. Comparison happens in your browser.
Paste the original on the left and the changed version on the right (or drop a file into each), then press Compare. Deleted lines are struck through in red ink, added lines are marked in green, and within a changed line the exact edited region is highlighted. Switch to the unified view for a classic patch-style reading, or copy it for a commit message or email.
Drop in a Word document and Proof Desk opens the Document view: the two files are laid out side by side with their formatting — headings, bold, lists, tables, and images, the way Draft Desk shows them — and the paragraphs that changed are tinted, added on the right in green and removed on the left in red. The Side-by-side and Unified views are still there for a line-level read.
Proof Desk started as a plain-text diff and is meant to keep learning formats. Today it reads plain text and code (.txt, .md, .csv, .json, .xml, source files) and Word documents (.docx — the text is pulled out with a hand-written ZIP + XML reader, the same machinery Draft Desk uses). Drop a .docx into either side and it compares as text. More formats (PDF, RTF, ODT) will land here rather than in a separate tool.
Flip on 🔍 Inspect and Proof Desk stops comparing and starts x-raying: it flags the characters that hide in pasted text and cause trouble — zero-width and other invisibles, bidirectional controls (the "Trojan Source" trick that makes code read one way and run another), no-break and other odd spaces, and homoglyphs (a Cyrillic "а" wearing a Latin "a"'s coat, the classic look-alike-domain phish). One button cleans a pane — stripping the invisibles and mapping look-alikes back to plain ASCII — while leaving your visible punctuation alone.
Most online diff tools send both texts to a server — a strange thing to do with contracts, unpublished writing, config files, or anything with names and secrets. This page has no server: the comparison runs as code in your browser tab, using a hand-written implementation of the same Myers algorithm Git uses. Save the page and it works with no internet connection at all.
Part of K-Engine Local Tools — free, privacy-respecting utilities that run on your device. The diff engine, ZIP reader, and DOCX extractor are hand-written; view-source and you're reading them. MIT licensed, from the K-Engine workshop · download the source.