Document compare for WindowsVisual redline100% on device
Compare two documents. See exactly what changed.
Drop an Original and a Revised document and Redlinr shows exactly what changed (deletions struck through in rose, insertions underlined in green) with an aligned split view and a plain-English summary. Nothing is uploaded: leases, offers and contracts never touch a web diff tool.
v1.1.3 beta · Windows 10 (1809+) & 11 · 64-bit · Installs without admin rights · No account
01 How it works
Drop it in. See what changed. Export it.
Drop in Original & Revised
Two labeled drop zones (Original and Revised) collapse into a compact header once both documents are loaded. Drag them in from File Explorer, or click a zone to browse. Word, PDF, RTF, ODT, HTML, Markdown or plain text, in any combination.
Redlinr compares
Paragraphs are aligned first, then a word-level diff runs only inside changed paragraphs, so even a long document stays fast. Everything happens locally; nothing is uploaded.
Review the redline
Inline strikethrough and underline, an aligned split view (1 / 2 to toggle), a "Change N of M" pager (N / P), moved-paragraph badges, and a plain-English headline with before→after value chips.
Export the redline
Save the redline as a single, self-contained HTML file (Ctrl E) to share. Your Original and Revised documents are never modified, moved, or deleted.
02 Features
Everything you need to see what actually changed.
One focused window that turns two documents into a clear redline, without ever sending either one to the cloud.
Redline, and an aligned split view
Deletions struck through, insertions underlined, right inline, in rose and green. Toggle to an aligned side-by-side split view of Original vs Revised when you'd rather read them in full.
A two-level diff that stays fast
Paragraphs are aligned first with a sequence matcher, then a word-level diff runs only inside changed paragraphs, so even large documents stay responsive. A single very long changed line falls back to a clean delete+insert instead of freezing the compare.
Change navigation pager
A floating "Change N of M" pager, with keyboard shortcuts (N / P), steps through every change one at a time, with a persistent highlight that follows along in the redline, the split view, and the sidebar.
Moved blocks, recognized
A paragraph that was relocated (not re-worded) is shown once with a "Moved" badge, instead of reading as a confusing deletion paired with an unrelated insertion.
Plain-English headline
A summary sentence surfaces the most significant changes at a glance, with paired before→after value chips for numbers, money, dates and percentages, the stuff you actually care about first.
Ignore case & whitespace
Two toggles re-run the compare with relaxed matching, so a re-wrapped paragraph or a capitalization tweak doesn't drown out the changes that matter, while the rendered text always shows exactly what's in the document.
Automatic reload
Redlinr notices when an open document changes on disk (say, a lease you just re-exported) and offers a one-click reload, via a banner, a header button, or Ctrl R.
Change summary sidebar
Words added and removed, and a clickable list of every change that jumps you straight to it in the redline, a fast way to triage a long document before you read it top to bottom.
Export the redline
Save the redline as a single, self-contained HTML file (viewable in any browser, no Redlinr required) with Ctrl E or the export button. Your Original and Revised documents are never modified, moved, or deleted.
Every common document format
Word (.docx), PDF, RTF, ODT, HTML, Markdown and plain text: mix and match either side. DOCX and ODT are read with a pure-Python OOXML/ODF reader, PDF text layers with pypdf, RTF with striprtf. There's no OCR, so a scanned PDF is reported as such rather than guessed at. Legacy binary
No OCR yet
.doc isn't readable yet; Redlinr suggests saving it as .docx.100% on your PC
No document (and no text from it) ever leaves your computer. No account, no cloud, no usage analytics. Web-based diff tools make you upload private files to someone else's server; Redlinr never does. The only network calls are the optional license check and update check.
Privacy
Built for everyone
Full keyboard control (1 / 2 to toggle Inline/Split, N / P to step through changes, Ctrl R to reload, Ctrl E to export), light, dark, or system-following appearance, Windows High Contrast support, and WCAG 2.1 AA contrast fixes measured and checked with axe-core.
WCAG 2.1 AA
Speaks your language
13 languages: English, Spanish, French, German, Italian, Portuguese (BR), Dutch, Polish, Russian, Turkish, Japanese, Simplified Chinese and Korean. Redlinr follows your Windows display-language list by default, and the toolbar picker (shown as language tags like EN or PT-BR rather than flags) overrides it and is remembered.
Localized
03 Reads & compares
DOCX
PDF
RTF
ODT
HTML
Markdown
TXT
04 Beta
You're testing the Windows build.
Redlinr has been on the Mac for a while. This is the Windows port: the same compare engine and the same redline guarantees, rebuilt on Windows APIs.
What would help most
Drag & drop, for real
Two documents at once, from File Explorer, the desktop, a search-results list, or a network drive.
Documents you actually work with
Your own leases, offers, contracts, reports. Check the redline against what you know actually changed, and tell me if it misses something or flags something that didn't change.
The install itself
Whether SmartScreen let you through, whether the shortcut and taskbar icon look right, whether uninstall leaves anything behind.
Anything that looks wrong
Clipped text, a scrollbar where there shouldn't be one, an odd translation, a dialog you couldn't reach with the keyboard.
06 Pricing
Free. For everyone.
Personal use is free forever: every format, unlimited comparisons, no key, no account, no watermarks. Free for commercial use at work too, no license required.
Personal
Free forever
For individuals and personal projects
- Compare unlimited documents, every supported format
- Read-only comparison: your originals are never modified
- Inline redline, split view, and plain-English summary
- 100% on-device, nothing uploaded
- No account, no nag screens
- Free updates forever
At work
Free commercial too
No license, no subscription
- Everything in Personal
- Use it commercially at work, free
- No license to buy, ever
- Free updates forever
- Supports solo indie development
Redlinr is free for everyone, including commercial use at work. There is no license to buy and no subscription.
07 Download & install
Get set up in about a minute.
Run the installer and Redlinr lands in your own user folder: no admin password, no UAC prompt, nothing else to install.
Version 1.1.3 beta · Redlinr-Setup.exe · about 16 MB · Free updates forever
Windows 10 (version 1809 or later) or Windows 11 · 64-bit
Everything Redlinr needs is inside the installer: no Python, no runtime to chase down. It does use the Microsoft Edge WebView2 Runtime to draw its interface, which ships with Windows 11 and reaches almost every Windows 10 machine through Windows Update. On the rare PC without it, Redlinr will say so on launch and Microsoft's free installer is a one-click fix.
No admin rights needed
Redlinr installs per-user into
%LOCALAPPDATA%\Programs\Redlinr, so there's no UAC prompt and no argument with your IT department. Uninstall from Settings → Apps → Installed apps like anything else.Windows may warn you the first time. Here's the honest story.
Redlinr is Authenticode-signed, so the publisher shows as a real, verified name rather than "Unknown publisher." But signing alone does not switch SmartScreen off: Microsoft builds reputation per file, and a brand-new build starts with none. Until this exact file has been downloaded enough times, you may still see a blue "Windows protected your PC" box.
- Click More info
- Check the publisher name shown
- Click Run anyway
08 FAQ
Common questions.
Is Redlinr really free?
Personal use is free forever: every supported format, unlimited comparisons, no account, no trial timer, no watermarks. If you use Redlinr at work, free for commercial use at work too, with no license to buy.
What file formats does it support?
Word (.docx), PDF, RTF, ODT, HTML, Markdown, and plain text, in any combination, so you can compare a .docx against a PDF export of the same document. DOCX and ODT are read with a pure-Python OOXML/ODF reader, PDFs through their text layer via pypdf, and RTF via striprtf. Legacy binary .doc files aren't readable yet. Redlinr will ask you to save it as .docx first.
Does Redlinr upload my documents anywhere?
No. Every compare runs entirely on your PC: no document, and no text from it, ever leaves your computer. There is no account and no usage analytics. The only times Redlinr contacts our server are to validate a business license key or to check for updates, which sends the app version.
Will Redlinr change my original files?
No. Comparing is read-only: Redlinr never modifies, moves, or deletes either the Original or the Revised file. The only file it ever writes is one you explicitly ask for: Export, which saves the redline as a new, self-contained HTML file.
What happens with a scanned PDF?
Redlinr reads a PDF's text layer via pypdf. A scanned, image-only PDF has no text layer, so Redlinr tells you plainly that this looks like a scanned PDF, which needs OCR that Redlinr doesn't do yet, rather than showing a blank or wrong result. That's an honest gap in this beta, not a hidden one.
Why did Windows show a blue "protected your PC" warning?
Because the file is new, not because it's unsigned. SmartScreen builds trust per file over downloads and time, and a fresh build starts from zero. Code signing gives you a verified publisher name in the dialog but does not skip it. Click More info → check the publisher → Run anyway. See the install section for the full explanation.
How do I update Redlinr?
It updates itself. Redlinr quietly checks about once a week and badges the update button when there's something new (never a pop-up), and you can turn the check off. Click it and Redlinr downloads the new installer, verifies its signature and version before running anything, installs over itself and reopens. If any of those checks fail it deletes the download and sends you here instead. Your settings carry over.
How is this different from the Mac version?
Same engine, same redline guarantees: this build was rebuilt on Windows APIs (pypdf, striprtf, a pure-Python OOXML/ODF reader) instead of macOS's textutil and PDFKit, reading documents into the same one-paragraph-per-line shape so the two diffs match. It launched at the Mac app's 1.1.3 feature set; a few things the Mac has picked up since (reading scanned PDFs with on-device text recognition, a color-blind-friendly palette, and a live-editable split view) haven't made it to this Windows build yet.
What about paragraphs that just moved, or differences in case and whitespace?
A paragraph that was relocated rather than reworded is shown once with a "Moved" badge, instead of reading as a confusing delete-and-insert pair. Separate Ignore case and Ignore whitespace toggles re-run the compare with relaxed matching so formatting-only differences don't drown out real changes. The text on screen always shows what's actually in the document.
How do I navigate a long document's changes?
A floating "Change N of M" pager, with
N / P keyboard shortcuts, steps through every change one at a time, with a persistent highlight that follows along in the inline redline, the split view, and the change summary sidebar.How does the business license work?
Redlinr is free for personal and commercial use. No license key needed. If you find it useful at work, you can support development from the tip jar at the bottom of the page.
Where do my settings live, and what does uninstalling remove?
Preferences sit in
%APPDATA%\Redlinr and your license key in your user profile. Uninstalling removes the app from %LOCALAPPDATA%\Programs\Redlinr; delete those two if you want every trace gone. Nothing is written outside your user account, and nothing goes in the registry beyond the uninstall entry.