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
KillerPDF
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, ~14.6 MB (ZIPs to 10.2MB), no runtime install required.
I hate Adobe. Acrobat is bloated, wants a subscription to do basic things, and phones home constantly. Most of the "free" alternatives are either ad-riddled, cloud-based, or rebrands of the same PDF engine sold under three different names.
KillerPDF is what I wanted: local-only, portable, no account, no telemetry. The PDF equivalent of Notepad.
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
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
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
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
Extract All Text to a .txt or .md file
Tesseract bundled in the single EXE; extra languages download on demand
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
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 8 languages (English, Spanish, Traditional and Simplified Chinese, German, French, Turkish, Bengali); contribute via Strings/TRANSLATING.md
Full keyboard shortcut overlay (Ctrl+?) with a link to the online guide
App & files
Single portable Windows EXE, ~6 MB zipped, no runtime install
Self-installs per-user to %LOCALAPPDATA% (no UAC), 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
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
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).
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.
