FileConverter (Local-Only)
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Best under ~2GB (device-dependent)

What is a .PDF file? (How to open & convert)

Learn what .PDF is, how to open it, and use an embedded local-only tool for common tasks.

Overview

.PDF PDF is designed to preserve layout across devices. It’s widely used for contracts, invoices, ebooks, and print-ready documents.

Basic info

  • Full name: Portable Document Format
  • Developer: Adobe (originally)
  • Category: Document

How to open a .PDF file

On macOS: Preview opens PDFs natively.

On Windows: Browsers open PDFs directly; Adobe Acrobat Reader is the common free reader.

On mobile: Mobile browsers and many reader apps support PDFs.

Try a related tool

Use a local-only tool (no uploads) for common tasks.

Technical characteristics

  • Can include text, vector graphics, images, fonts, forms
  • Not meant for easy editing (hence Word conversions)
  • Size depends heavily on embedded images and compression

Common scenarios

  • Merging multiple PDFs into one file
  • Adding page numbers before printing
  • Generating PDFs from text or templates

Security notes

PDFs can contain complex content. Only open PDFs from trusted sources and keep your viewer updated.