KillerPDF is a lightweight PDF viewer and toolkit designed to simplify PDF management and editing on Windows. It offers high-quality rendering, merge/split functionality, inline text editing, and annotation tools for seamless document manipulation.
Key Features:
High-Quality Rendering: Utilizes the PDFium library for crisp and accurate PDF display.
Merge/Split Functionality: Drag-and-drop to combine files or extract specific pages.
Inline Text Editing: Edit text with font matching for a polished, professional look.
Annotation Tools: Add text boxes, draw freehand, highlight, and insert signatures.
Page Management: Crop, rotate, rearrange, or delete pages with intuitive controls.
Audience & Benefit:
Ideal for professionals, students, and anyone needing reliable PDF tools without bloat. KillerPDF provides a portable, open-source solution that requires no subscription, runtime installation, or admin rights. Install via winget or run in portable mode, ensuring flexibility and ease of use.
README
Free and open-source PDF editor for Windows. View, annotate, OCR, merge, split, edit text, draw, sign, fill forms, print, flatten, and open password-protected PDFs without an Adobe subscription or a phone-home. Install or run portable. Single Windows EXE, ~15.9 MB (ZIPs to 11.4MB), no runtime install required.
Features
Viewing & navigation
High-quality rendering via PDFium
Four view modes - Single Page, Continuous scroll, Two-Page, and Grid - that persist across sessions
Tabbed documents: open several PDFs at once, each restoring its page, zoom, and view mode
Split pane (F10): two documents side by side in one window, each pane with its own tab strip - drag a tab across to move it
Full-text search across the whole document with highlighting; drag-select to copy text
Outline/bookmark navigation and clickable links, including internal cross-references and TOC back-links
Bookmark editing in the sidebar: add, inline-rename, nest, reorder, retarget, and delete - with multi-select and full undo
Jump history: Alt+Left / Alt+Right and the mouse back / forward buttons retrace bookmark, link, and page jumps, browser-style; Home / End jump to the first / last page
Zoom presets with scroll-wheel sync; Fit to Width and Fit Page re-apply on resize
Full-screen mode (F11) hides all chrome so only the document fills the screen
Recent files on the start screen and Open menu, each with its real Windows file-type icon
Annotate & edit
Inline text editing with font matching against the original document
Resizable, word-wrapping text boxes with an optional whiteout background fill
Freehand draw, a straight-line tool, and highlight - each with its own color, opacity, and width
Full RGB color picker: saturation/value square, hue strip, hex input, screen eyedropper, and editable palette
Select tool to move, resize, multi-select, and restyle any annotation in place
Undo and redo (Ctrl+Z / Ctrl+Y) across annotations, text edits, stamps, and document-level operations, tracked per tab
Insert images as resizable annotations, burned into the PDF on save
Page-number and watermark stamping across a page range, applied as one undo
OCR (built in, no cloud)
OCR a whole page or a dragged region straight to the clipboard
Make Searchable PDF: lay an invisible text layer over a scan
Tesseract bundled in the single EXE; extra languages download on demand
Organize pages
Merge multiple PDFs and split out selected pages, with drag-and-drop reordering
Right-click sidebar: insert blank page, rotate, move, extract, or delete - on multi-page selections
Crop with corner handles; remove crop from one page or all
Transform: rotate by 90 degrees or a fine angle, scale, flip, and straighten a crooked scan by drawing a level line - live preview, with annotations following the transform
Drop a folder or .zip onto the window to merge the PDFs and images inside into one, or open each separately
Forms & signing
Fill PDF forms (text, checkbox, radio) as live controls and save back to the PDF
Digital signatures with a cloud certificate (Certum SimplySign), including click-to-sign form fields
Draw and reuse signatures and initials, or import a PNG/JPG/BMP to place anywhere
Output
Print with annotations flattened, a real in-app preview, and scale / position / margins / pages-per-sheet / color / two-sided options, rendered at 300 DPI
Save Flattened PDF: rasterize every page into a fully uneditable document
Document Info: view and edit title, author, subject, keywords, and creator metadata
Command line
Every core operation also runs headless from a terminal - no window, meaningful exit codes (0 success, 1 failed, 2 bad usage), and it works even while the app is open:
Each command reuses the exact pipeline its GUI equivalent runs - merges rewrite named-destination links, saves scrub the same structural hazards, OCR languages download on first use. Full reference on the help page.
Customize
Six themes - Dark, Light, Black, Blood, Greed, Cyanotic - with per-theme accent colors, switchable live
Toolbar style (icon size, text placement) and a resizable sidebar that docks left or right
Localized UI in 10 languages (English, Spanish, Traditional and Simplified Chinese, German, French, Turkish, Bengali, Japanese, Czech); contribute via TRANSLATING.md
Full keyboard shortcut overlay (F1 or Ctrl+?) with a list view and a visual keyboard view, color-coded by category, plus a link to the online guide
App & files
Single portable Windows EXE, ~15.9 MB, no runtime install
Per-user OR all-user install: self-installs per-user to %LOCALAPPDATA% (no UAC), or machine-wide to Program Files for every account (one admin prompt, /silent for scripted deployment); registers as a PDF handler with a branded file icon and uninstalls cleanly via Add/Remove Programs
Opens password-protected PDFs (prompts instead of erroring) and repairs damaged ones
Standards-safe saves: every release is validated with veraPDF across a 2,900-file conformance corpus with a zero-regressions bar - see validation/RESULTS.md
Local-only: no account, no telemetry, no phone-home
Screenshots
Requirements
Windows 10 or 11 (x64)
No runtime install. Everything needed is inside the EXE (targets .NET Framework 4.8, which ships with every supported Windows release).
Download
WinGet:
winget install killerpdf
Chocolately:
choco install killerpdf
Prebuilt binary:
Source (GPL3 corresponding source for this release):
Build from source
git clone https://github.com/SteveTheKiller/KillerPDF.git
cd KillerPDF
dotnet publish -c Release
Output lands in bin/Release/net48/publish/. The publish step produces a single Costura-bundled KillerPDF.exe plus a versioned KillerPDF--src.zip for GPL3 source distribution.
Requires the .NET 8 SDK or later to build (even though the output targets .NET Framework 4.8).
The PDF write engine (PdfSharpCore, MIT) is vendored under third_party/PdfSharpCore/ and builds as part of the solution; it carries six standards-conformance patches, each marked KillerPDF patch in the source. Origin commit and details are recorded in third_party/PdfSharpCore/VENDORED.txt.
GPLv3. See LICENSE. If you fork, modify, or redistribute KillerPDF, your version must also be released under GPLv3 with source available. No exceptions for commercial rebrands.
