Format at a glance
- Full name
- Portable Document Format
- File extensions
- MIME types
- application/pdf
- Category
- Documents
- Compression
- Depends on the contained codec
- Transparency
- Depends on the content
- Animation
- No
- Properties
- Multiple pages, Color profiles
Suitable tools
What is this format?
Portable Document Format describes pages rather than only storing a screenshot. Content may remain searchable and selectable, or a page may consist solely of scanned image data.
PDF supports several compression methods for different objects. Its final size therefore depends on embedded images, fonts, object structure and optional features rather than one universal quality setting.
What is it used for?
- Contracts, invoices and official documents
- Print-ready layouts and manuals
- Forms and digitally signed documents
- Scanned documents and searchable OCR copies
Which programs can open it?
- Adobe Acrobat Reader
- Chrome, Edge, Firefox and Safari
- macOS Preview
- Okular, Evince and other desktop PDF viewers
Support across devices and browsers
Browsers, Edge and dedicated readers open PDF directly.
Preview and Safari provide native viewing and annotation tools.
Okular, Evince and browsers provide broad support.
Browsers, Google Drive and reader apps open PDF.
Files, Books, Safari and reader apps open PDF.
Current browsers include PDF viewers, although advanced forms and signatures may require dedicated software.
Advantages
- Stable page layout across platforms
- Can combine text, vectors, images and fonts
- Broad support for viewing, printing and archiving
Disadvantages
- Editing is harder than editing the source document
- Scanned PDFs may not contain searchable text
- Complex forms, signatures, encryption or multimedia are not supported equally by every viewer
Comparison with alternatives
PDF preserves fixed pages; EPUB usually reflows text to the reader's screen and font settings.
PNG stores one raster image; PDF can contain many pages and selectable text or vectors.
SVG describes one scalable graphic; PDF is a paginated document container.
LocalFileLab support
PDF.js and PDF libraries read pages locally in the browser.
LocalFileLab can create PDF from compatible images, text and supported documents.
Light mode restructures objects; stronger modes rasterize pages and may remove searchable text.
An embedded local PDF preview is available.
Basic document metadata can be removed during compression; not every PDF metadata structure is preserved or editable.
Related formats
Frequently asked questions
Why can I not select text in a PDF?
The page may be a scan consisting only of pixels. OCR is required to create a searchable text layer or extract text.
Does compressing a PDF reduce quality?
It depends on the method. Object cleanup can be lossless, while rasterizing or recompressing page images reduces fidelity and can remove selectable text.
Can every PDF be edited?
No. Permissions, signatures, flattened content, missing fonts and scan-only pages can limit editing.