Open PDF Studio

A free, open-source PDF editor and annotator for Windows, macOS, Linux, and Android.

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Open PDF Studio is a lightweight, native desktop application that provides professional-grade PDF annotation, markup, and editing tools without subscriptions, telemetry, or bloatware. Built with Tauri 2 and web technologies, it delivers a fast, modern experience with a Microsoft Office-style ribbon interface.

Repository activity

Latest Star History overview showing the ongoing growth of this active open-source project.

Why Open PDF Studio?

Professional annotation, markup, measurement, redaction and page management — the tools that typical commercial PDF editors lock behind a subscription or a paid tier — are all included, free and fully open source. No subscriptions, no telemetry, no watermarks.

	Open PDF Studio	Typical commercial PDF editors
Price	Free & open source (LGPL-3.0)	Subscription or paid license
Annotations & markup	All included	Often a paid tier
Measurement tools	Included	Usually paid
Stamps, watermarks & redaction	Included	Usually paid
Page management	Included	Usually paid
Multi-tab editing	Included	Varies
Telemetry	None	Common
Platforms	Windows, macOS, Linux, Android	Varies (often fewer)

Features

Annotations & Markup (20+ Tools)

• Text markup: Highlight, underline, strikethrough
• Shapes: Rectangle, ellipse, polygon, cloud, cloud polyline, line, arrow, polyline
• Hatch fill patterns: Cross-hatch, diagonal, dots, and more for shape fills
• Freehand drawing: Pen tool with configurable color, width, and opacity
• Text annotations: Text box, callout with leader line, sticky notes with popup editing
• Stamps: 10 built-in stamps (Approved, Rejected, Draft, Confidential, Final, etc.)
• Images: Insert from file, paste from clipboard, or drag-and-drop, with non-destructive cropping
• Signatures: Draw multi-stroke signatures, save up to 5 for quick reuse
• Redaction: Mark areas and apply to permanently remove content

Measurement Tools

• Distance, area, and perimeter measurement
• Scale calibration dialog with mm, cm, m, inches, feet, and points
• Per-line scale override, with fallback to the document scale
• Quick scale: right-click a dimension line and type a value (e.g. "12.3m") to recalibrate
• Draggable dimension text and endpoints with live recalculation
• Object snapping to endpoints, midpoints, centers, and edges
• Angle snapping with configurable increments

Screenshot

• Capture full page or a selected region as an image
• Copy to clipboard or save to file

Crop Margins

• Auto-detect and trim whitespace around page content

Text Editing

• Edit existing PDF text content inline
• Add new text annotations with font, size, and color control

Page Management

• Insert blank pages (standard or custom sizes)
• Delete, extract, and replace pages
• Reorder pages via drag-and-drop thumbnails
• Merge multiple PDFs into one
• Page rotation (90/180/270 degrees)

Watermarks & Headers/Footers

• Text and image watermarks with opacity, rotation, and position control
• Headers and footers with variables ({page}, {pages}, {date}, {time}, {filename})
• Apply to all pages or specific ranges

Forms

• Fill interactive PDF forms (AcroForms and XFA)
• Create text fields, checkboxes, and radio buttons
• JavaScript validation support

Printing

• Full print dialog with live preview
• Page range, subset (odd/even), reverse order, copies, and collation
• Scaling: fit to page, actual size, or custom percentage
• Print content: document only, markups only, or both
• Print as image option
• Virtual printer installation (Windows)

Export

• Export pages as PNG or JPEG (72, 150, 300, 600 DPI)
• Export as raster PDF
• Export/import annotations as XFDF

Find & Search

• Text search with match case and whole word options
• Highlight all matches with result count
• Navigate results with F3

Format & Styles

• 12 pre-defined style gallery for quick annotation styling
• Fill color, stroke color, line width, opacity, and border style
• Blend modes for annotation compositing
• Per-annotation-type default styles

Multi-Select & Alignment

• Select multiple annotations with rubber band or Ctrl+Click
• Shared property editing across selected annotations
• 6-point alignment (left, center, right, top, middle, bottom)
• Horizontal and vertical distribution
• Match size (width, height, or both)
• Flip horizontal/vertical and rotate selected annotations
• Z-order control (bring to front/back, forward/backward)

Object Snapping

• Snap to endpoints, midpoints, centers, and edges
• Snap to in-progress vertices while drawing polylines and measurements
• Configurable snap radius (3-30px)
• Angle snapping (1-90 degree increments)
• Optional grid overlay with grid snapping

Tool Palette

• Floating or dockable toolbar with all annotation tools
• Dock to left or right side of the canvas
• Quick access without switching ribbon tabs

PDF Viewing & Navigation

• High-quality native rendering via a multi-process PDFium worker pool — off the UI thread and crash-isolated, so a bad page never freezes or takes down the app
• Progressive tile rendering for very large CAD drawings: the page and its thumbnails fill in tile-by-tile across the worker pool instead of a seconds-long blank wait
• View modes: single page, continuous scroll, and book (two-page spread, page 1 on the right)
• Zoom: fit page, fit width, actual size, custom percentage, and cursor-anchored mouse-wheel zoom
• Page navigation: first, previous, next, last, go to page
• PDF/A compliance detection with read-only enforcement
• Digital signature validation panel

Left Panel (10 Tabs)

Thumbnails, Bookmarks, Annotations, Attachments, Digital Signatures, Layers, Form Fields, Named Destinations, Links, Tags

Bookmarks

• Create, edit, and delete bookmarks
• Hierarchical tree with expand/collapse
• Custom colors and text styling (bold, italic)

Document Management

• Multi-tab interface for multiple PDFs
• Session save/restore (named workspace snapshots)
• Open PDF from URL
• Bookmarked folder places for quick file access
• Recent files with pin/unpin
• Unsaved changes detection with save prompt
• Document properties dialog
• File locking to prevent external writes

Ribbon Interface (7 Tabs)

Home, Comment, View, Organize, Arrange, Format, Help

Customization

• 5 themes: Dark, Light, Blue, High Contrast, System (auto-detect)
• 39 languages including RTL support: Arabic, Bengali, Bulgarian, Catalan, Chinese, Croatian, Czech, Danish, Dutch, English, Finnish, French, German, Greek, Hebrew, Hindi, Hungarian, Indonesian, Italian, Japanese, Korean, Malay, Norwegian, Farsi (Persian), Polish, Portuguese, Romanian, Russian, Serbian, Slovak, Spanish, Swahili, Swedish, Tamil, Thai, Turkish, Ukrainian, Urdu, Vietnamese
• Configurable preferences dialog

Undo/Redo

• Up to 100 levels per document
• Covers annotations, page operations, watermarks, and text edits

Auto-Update

• Built-in update checker with download progress
• Skip version or remind later options
• Automatic installation and relaunch

Keyboard Shortcuts

Shortcut	Action
Ctrl+N	New document
Ctrl+O	Open file
Ctrl+S	Save
Ctrl+Shift+S	Save As
Ctrl+P	Print
Ctrl+Z	Undo
Ctrl+Y / Ctrl+Shift+Z	Redo
Ctrl+F	Find
F3	Find next
Ctrl+A	Select all annotations on page
Ctrl+C / Ctrl+V	Copy / Paste annotations
Delete	Delete selected annotation(s)
Ctrl+D	Document properties
Ctrl+W	Close active tab
V	Select tool
H	Hand tool
T	Text box tool
N	Sticky note tool
Ctrl+= / Ctrl+-	Zoom in / Zoom out
Ctrl+0	Actual size
Ctrl+1	Fit width
Ctrl+2	Fit page
F9	Toggle navigation panel
F11	Toggle annotations list
F12	Toggle properties panel
F1	Keyboard shortcuts
Arrow keys	Nudge annotation (1px, Shift for 10px)
Enter	Complete area/perimeter measurement

Installation

Windows

Download the latest .exe installer from Releases.

macOS

Download the latest .dmg (universal binary for Intel and Apple Silicon) from Releases.

Linux

Snap (Ubuntu App Center):

sudo snap install open-pdf-studio

Debian/Ubuntu (.deb):

sudo dpkg -i open-pdf-studio_*.deb

AppImage:

chmod +x open-pdf-studio_*.AppImage
./open-pdf-studio_*.AppImage

Android

Download the APK from Releases.

Building from Source

Prerequisites

• Node.js 20+
• Rust (stable)
• System dependencies:
  • Linux: libwebkit2gtk-4.1-dev libappindicator3-dev librsvg2-dev patchelf
  • macOS: Xcode Command Line Tools
  • Windows: Visual Studio Build Tools with C++ workload

Build

cd open-pdf-studio
npm install
npx tauri build

The built application will be in open-pdf-studio/src-tauri/target/release/bundle/.

Development

cd open-pdf-studio
npm install
npx tauri dev

Tech Stack

Layer	Technology
Desktop framework	Tauri 2 (Rust backend)
UI framework	SolidJS
Build tool	Vite
Page rendering	Multi-process PDFium worker pool, with progressive tiling for large drawings
Text layer & structure	PDF.js
PDF manipulation	pdf-lib

Contributing

Contributions are welcome. Please open an issue to discuss proposed changes before submitting a pull request.

License

Open PDF Studio is licensed under the GNU Lesser General Public License v3.0.

PDF.js is licensed under the Apache License 2.0. pdf-lib is licensed under the MIT License. PDFium is licensed under the BSD 3-Clause License.