10 Best Free PDF Tools in 2026 — Sign, Edit, Merge & More

The Best Free PDF Tools You Can Use Right Now

PDF is the universal document format, but working with PDFs often feels like it requires expensive software. It does not. There are excellent free tools for every PDF task — signing, editing, merging, splitting, compressing, converting, and more.

This guide covers the 10 best free PDF tools available in 2026, organized by what you need to do. Every tool listed here is genuinely free (not a "free trial" that expires in 7 days).

1. SigPDF — Best Free PDF Signer

What it does: Sign PDF documents in your browser

SigPDF is a browser-based PDF signing tool that lets you add your signature to any PDF without creating an account or installing software. The signing tool is free to use — draw your signature with your mouse or finger and place it on the document. Downloading signed PDFs requires a subscription from €2.08/month.

Why it stands out:

• No account or registration required
• Files are processed entirely in your browser — nothing is uploaded to a server
• No usage limits or watermarks
• Works on any device with a browser
• Takes under 60 seconds

Best for: Signing contracts, forms, agreements, and any document that needs your signature.

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2. LibreOffice Draw — Best Free PDF Editor

What it does: Edit PDF content (text, images, layout)

LibreOffice Draw can open PDFs and let you edit the actual content — change text, move elements, add images, and modify the layout. It is part of the free, open-source LibreOffice suite.

Why it stands out:

• Truly free and open source
• Available on Windows, Mac, and Linux
• Can edit text directly in PDFs
• Full drawing and image editing tools
• No account or subscription required

Limitations:

• Complex PDF layouts may not render perfectly
• Heavier than necessary for simple tasks
• Export-as-PDF workflow adds steps

Best for: Making content changes to PDFs when you need to alter text, images, or layout.

3. PDF Arranger — Best Free PDF Page Manager (Linux)

What it does: Rearrange, rotate, delete, and merge PDF pages

PDF Arranger is a lightweight, open-source tool for Linux that provides a visual drag-and-drop interface for managing PDF pages. You can reorder pages, rotate them, delete unwanted pages, and merge multiple PDFs together.

Why it stands out:

• Extremely lightweight and fast
• Intuitive visual interface
• Handles merging and splitting in one tool
• Open source

Limitations:

• Linux only (though it can run on Windows with some effort)
• Cannot edit PDF content — only page-level operations

Best for: Linux users who need to reorganize PDF pages or combine multiple PDFs.

4. iLovePDF — Best Free Online PDF Multi-Tool

What it does: Merge, split, compress, convert, and perform many other PDF operations online

iLovePDF is a web-based suite of PDF tools. It handles an impressive range of tasks: merging, splitting, compressing, converting to and from various formats (Word, Excel, PowerPoint, JPG), rotating, adding page numbers, watermarking, and more.

Why it stands out:

• Wide range of tools in one platform
• Clean, easy-to-use interface
• No installation required
• Handles conversions between PDF and other formats

Limitations:

• Free tier has usage limits (a handful of operations per hour)
• Files are uploaded to iLovePDF servers
• Account required for some features
• Premium features locked behind a $7/month paywall

Best for: Occasional PDF conversions and batch operations when you do not mind server-side processing.

5. Stirling PDF — Best Self-Hosted PDF Suite

What it does: A full PDF toolbox that you host on your own server

Stirling PDF is an open-source, Docker-based PDF tool suite. It provides merge, split, convert, compress, sign, and many other PDF operations through a web interface — all running on your own hardware.

Why it stands out:

• Complete control over your data — runs on your server
• No file size limits
• No usage limits
• Active open-source community
• Huge feature set (50+ operations)

Limitations:

• Requires Docker and a server (or local machine) to run
• Setup is more technical than a web-based tool
• Not suitable for non-technical users

Best for: Tech-savvy users or organizations that want a full PDF toolkit without sending files to third-party servers.

6. Okular — Best Free PDF Reader and Annotator (Desktop)

What it does: Read, annotate, and review PDFs

Okular is KDE's document viewer. It handles PDFs, ePubs, and other document formats with robust annotation tools — highlighting, underlining, text notes, stamps, and freehand drawing.

Why it stands out:

• Feature-rich annotation tools
• Lightweight and fast
• Supports many document formats beyond PDF
• Open source
• Available on Linux, Windows, and Mac

Limitations:

• Annotations are saved separately from the PDF by default (though you can save them into the PDF)
• Cannot edit PDF content
• Interface may feel dated on non-KDE desktops

Best for: Reading and annotating PDFs, reviewing documents, and academic work.

7. Xournal++ — Best Free PDF Handwriting Tool

What it does: Add handwritten notes, annotations, and signatures to PDFs

Xournal++ excels at freehand annotation. It is designed for drawing tablet users and turns a PDF into a canvas for handwriting, sketching, and note-taking. You can also use it to sign PDFs on Linux.

Why it stands out:

• Excellent pressure-sensitive drawing tablet support
• Smooth pen and highlighter tools
• Layer support for complex annotations
• Open source and actively developed

Limitations:

• Requires installation
• Best with a drawing tablet (mouse input works but is less natural)
• Cannot edit PDF text — annotation only

Best for: Students, researchers, and anyone who annotates PDFs with handwritten notes or drawings.

8. Ghostscript + Command Line — Best Free PDF Compressor

What it does: Compress PDF file sizes from the command line

Ghostscript is the open-source backbone of many PDF tools. Used from the command line, it can dramatically reduce PDF file sizes by resampling images and optimizing the internal structure.

A practical compression command:

gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook -dNOPAUSE -dBATCH -sOutputFile=compressed.pdf input.pdf

The -dPDFSETTINGS flag controls quality:

• /screen — Lowest quality, smallest file size (72 dpi)
• /ebook — Good balance of quality and size (150 dpi)
• /printer — High quality (300 dpi)
• /prepress — Maximum quality, largest file size

Why it stands out:

• Extremely effective compression
• Scriptable and automatable
• Free and open source
• Available on every platform

Limitations:

• Command line only — no graphical interface
• Syntax is not intuitive
• Can degrade image quality if settings are too aggressive

Best for: Developers, system administrators, and power users who need to compress PDFs in automated workflows.

9. Firefox / Chrome Built-In PDF Viewer — Best for Quick PDF Viewing

What it does: View PDFs and fill interactive form fields directly in your browser

Every modern browser has a built-in PDF viewer. Firefox's pdf.js implementation is particularly capable — it can render PDFs, fill interactive form fields, and even add basic annotations.

Why it stands out:

• Already installed on your computer
• No additional software needed
• Fast and lightweight
• Handles interactive form fields well

Limitations:

• Cannot add signatures (in most browsers)
• Cannot edit PDF content
• Cannot handle non-interactive form fields
• Limited annotation capabilities

Best for: Quickly viewing PDFs and filling out interactive forms without opening a separate application.

10. pdftk (PDF Toolkit) — Best Free Command-Line PDF Multi-Tool

What it does: Merge, split, rotate, stamp, encrypt, and manipulate PDFs from the command line

pdftk is the Swiss army knife of command-line PDF tools. It can merge PDFs, split them into individual pages, rotate pages, add watermarks, encrypt and decrypt, fill form fields, and more.

Common commands:

# Merge two PDFs
pdftk file1.pdf file2.pdf cat output merged.pdf

# Extract pages 1-5
pdftk input.pdf cat 1-5 output extract.pdf

# Rotate all pages 90 degrees
pdftk input.pdf cat 1-endeast output rotated.pdf

# Add a password
pdftk input.pdf output protected.pdf user_pw mypassword

Why it stands out:

• Extremely versatile
• Scriptable for batch operations
• Stable and well-documented
• Free and open source

Limitations:

• Command line only
• Cannot edit PDF content
• Cannot add signatures
• Syntax takes time to learn

Best for: Developers and power users who frequently manipulate PDFs in scripts and automated workflows.

Choosing the Right Tool

| Task | Best Free Tool | |------|---------------| | Sign a PDF | SigPDF | | Edit PDF content | LibreOffice Draw | | Merge/split PDFs | PDF Arranger (Linux) or pdftk (CLI) | | Compress a PDF | Ghostscript | | Convert PDF to Word | iLovePDF | | Annotate a PDF | Okular or Xournal++ | | Fill a PDF form | Browser built-in viewer or SigPDF | | View a PDF | Firefox/Chrome built-in | | Self-hosted PDF toolkit | Stirling PDF | | Command-line PDF ops | pdftk |

The PDF Does Not Have to Be Painful

You do not need to pay for expensive software to work with PDFs. The tools above cover every common PDF task — and they are all genuinely free.

For signing PDFs specifically, SigPDF remains the fastest option. No account, no installation, no files leaving your browser. Just your signature on your document.

Sign Your PDF Now →