Free PDF markup, measuring and editing for construction and engineering, on Windows
Open source (AGPL), no account, no telemetry, portable.
Download for Windows · Getting started · Report a bug · Code signing policy
Version 1.0: KanzonasPDF is used daily for real work, and every build is tested automatically. It's still young and actively developed: please tell us when something doesn't work, and keep a copy of important files.
People who mark up and measure drawings and plans, estimators, engineers, architects, reviewers, and anyone who wants a capable PDF editor without a license or a subscription. If you need Bluebeam-style calibration, lengths, areas, volumes and revision clouds, or Acrobat-style forms, signatures, redaction and text editing, but not the price, try it.
| KanzonasPDF | Bluebeam Revu | Adobe Acrobat Pro | PDF-XChange Editor | |
|---|---|---|---|---|
| Price | Free, open source | Subscription | Subscription | Free with watermarks, or a license |
| Calibrated measuring (length, area, volume, count) | Yes | Yes | Basic | Yes |
| Compare revisions (clouds the changes) | Yes | Yes | Yes | Yes |
| Edit page text and objects | Yes (one line at a time) | Limited | Yes | Yes |
| Portable (USB stick, nothing in the registry) | Yes | No | No | Yes |
| Runs offline, no account | Yes | Account | Account | Yes |
Those are capable, mature products with features KanzonasPDF doesn't have (see Known limitations). The table is about what you get for free.
Works today: tabs, markups, measuring, stamps, page tools, forms, text editing, OCR, digital signatures, compare, redaction, a portable build and a PortableApps.com package.
Not yet: a code-signed installer (SmartScreen warns the first time), a proven redaction corpus, or every feature of the products above. Check the result before you send a drawing out.
Read and navigate
- Tabs, fast scrolling and zoom even on huge CAD sheets, page thumbnails, bookmarks, layers
- Find with every match highlighted; split view to see two places at once
- Light, dark or match-Windows theme; ribbon or classic toolbars
Mark up and review
- Highlight, underline, strike out, comment on text, sticky notes, text boxes, callouts
- Rectangles, ellipses, revision clouds, polygons, lines, arrows, freehand pen
- Stamps (Approved, Reviewed, Draft and more, or your own), with your name and the date
- A tool chest of saved markup styles, a markups list you can filter and export, and Compare documents: word by word for text that reflows, or laid over each other for drawings
- Markups are standard PDF annotations, so Acrobat and other viewers see them too
Measure (for drawings and plans)
- Set the scale from a preset (1/4" = 1'-0", 1:100, ...) or by calibrating a known dimension
- Length, polylength, area and perimeter, and counts, with a measurement summary you can export to CSV
- CAD-style mouse (the wheel zooms, hold it to pan) and snapping to the drawing
Edit the PDF itself
- Edit text in place; move, resize, rotate or delete the page's own pictures and vector shapes
- Erase content in an area, capture an area as sharp vector content, add backgrounds, watermarks, headers and footers, page numbers and Bates numbering
- Pages: rotate, reorder, insert, extract, combine files
Sign, protect and clean up
- Your signature and initials (drawn or scanned), digital signatures with a certificate, passwords and permissions
- Redaction removes marked text and, by default, scrubs metadata, attachments, hidden text and scripts. It is not a proven redaction corpus: check the result before sharing.
- Recognize text (OCR) in scanned pages, offline
Forms and export
- Fill in and create forms
- Export to Word, Excel, PowerPoint, AutoCAD DXF, images and text
Built to stay fast and light: it starts in well under a second, and every build checks start-up time and memory automatically. There's no background service, no account and no telemetry. It only goes online to check whether a newer version exists (you can turn that off) and, if you add a trusted timestamp to a digital signature, to contact a timestamp server.
Download from the Releases page. Pick one of these files from the newest release:
| File | What it is |
|---|---|
KanzonasPDF-v…-setup.exe |
Installer (recommended). No administrator rights needed. It can add a desktop shortcut and offer KanzonasPDF as an app for opening PDFs. |
KanzonasPDF-portable.zip |
No installation. Unzip anywhere (even a USB stick) and run KanzonasPDF.exe. Settings, signatures and stamps stay in a data folder next to it. To update, unzip the new one over the same folder: the program keeps the same path, so it stays your default PDF app. |
KanzonasPDF-windows.zip |
The same program as the portable version, but it keeps its settings in your Windows profile. |
Also available as a PortableApps.com package
(KanzonasPDFPortable_<version>_English.paf.exe on the Releases page, in testing on their
forum) and, soon, through winget (the manifests are in packaging/winget).
KanzonasPDF isn't code-signed yet (see the code signing policy), so Windows SmartScreen may warn you the first time you run it, simply because it doesn't recognize a new program yet. To run it anyway, click More info, then Run anyway. Even signed, a new program can see this warning for a while, until Windows has seen enough people run it safely.
Only do this with files downloaded from this project's
Releases page. Every release is built
from the public source code in this repository by GitHub's own build servers and tested there
before it's published, and every release lists the SHA-256 checksum of each download
(SHA256SUMS.txt), so you can check that what you downloaded is what was built:
Get-FileHash <file> in PowerShell.
- KanzonasPDF tells you when a newer version is out (Help > Check for updates...). It only tells you; it never installs anything by itself.
- To update, run the new installer: it replaces the old version and keeps your settings, signatures, stamps and tool chest.
- To uninstall, use Windows Settings > Apps.
- Open a PDF: drag it onto the window, or File > Open. Several PDFs open as tabs.
- The user manual is built in: press F1 (Help > User manual). It covers every tool, menu command and keyboard shortcut.
- Make it yours: File > Preferences (Ctrl+K) has your name for markups, your signature, default markup styles, the zoom documents open at, mouse and scrolling options, automatic backups and more.
- Keyboard shortcuts: View > Keyboard shortcuts... lists them all, and you can change them.
- Found a bug or have an idea? Open an issue. Please describe what you did and what happened, and don't attach confidential PDFs.
- Security problem (redaction, passwords, signatures): please report it privately, as described in SECURITY.md.
- Want to contribute? See CONTRIBUTING.md and the Code of Conduct.
- Like it? If KanzonasPDF saves you time, a ⭐ star on GitHub (top right of this page) helps other people find it, and telling a colleague helps even more.
- Windows only.
- Saving changes to a digitally signed file invalidates its signatures (an unchanged signed file is saved as an exact copy).
- Text editing works one line at a time; it doesn't reflow the rest of a paragraph. If the original font isn't available, a close standard font is used.
- Edit objects works on pictures and vector shapes, not on text, and not on content grouped inside form XObjects.
- Password permissions are honored by Acrobat, PDF-XChange and this app, but they aren't tamper-proof; use a digital signature to prove a file hasn't changed.
- A personal certificate proves a document is unchanged, but other people's software shows your identity as verified only if they trust your certificate (or you use one from a certificate authority). Windows Personal-store signing supports RSA/ECDSA keys; smart-card/token availability depends on the installed Windows key provider and hardware.
- Export: Word works best for ordinary text documents; Excel needs real (not scanned) tables; PowerPoint slides are page pictures; AutoCAD export is DXF (not DWG) and leaves out images.
- OCR uses overlapping tiles and caps large sheets at 13000 px on the long side, so very small text on big drawings may be missed.
KanzonasPDF is written in Python with PyMuPDF (MuPDF) and Qt (PySide6). Project rules for changes are in CLAUDE.md.
Run from source (Windows): install Python 3.10+ from https://www.python.org/downloads/
(tick "Add to PATH"), then double-click Start KanzonasPDF.bat (the first time, it installs
the libraries it needs). Or: pip install -r requirements.txt, then python run.py.
Self-test: python -m kanzonas --selftest selftest.log checks the main features, the
manual and the performance budget. The Windows build runs it on the packaged app, the installer
and an upgrade.
Build an .exe: double-click build_windows.bat; the app ends up in
dist\KanzonasPDF\KanzonasPDF.exe.
Releases publish themselves: when main gets a new __version__ (in
kanzonas/__init__.py), usually by merging a pull request, and the build passes, the tested
installer and zips are published as a draft release v<version> (a pre-release while the
version is 0.x), unless the repository variable AUTO_RELEASE is true. A tag build (v*)
publishes a real release. Other branches build and test but don't publish. Set AUTO_RELEASE
to false (Settings > Secrets and variables > Actions > Variables) to turn releasing off.
CAD test drawings: python tests/cad_samples.py DIR generates realistic plotted CAD sheets
(including a 42x30 site plan with ~139,000 contour segments and a scanned sheet);
python tests/cad_battery.py DIR runs the app's features against them and prints timings.
App icon and logo: the owner's artwork in assets/ (after changing them, run
python tools_make_assets.py). Toolbar icons: the Material Design Icons font that ships with
QtAwesome.
Official KanzonasPDF releases stay free of charge for personal and commercial use: no subscriptions, trial expiration, paid feature tiers, required account or required paid cloud service. Optional donations never unlock features. This is the project's promise; the license below is what lets anyone use, change and share the code (it doesn't by itself stop others from charging for copies they make).
KanzonasPDF is free software under the GNU AGPL-3.0. It's built on PyMuPDF, which is AGPL-3.0, so KanzonasPDF's source code is always available here.