PDF Document — Portable Document Format for fixed-layout documents across platforms.
Quick facts
What is .pdf
A .pdf file is a PDF Document — Portable Document Format for fixed-layout documents across platforms.
In the mime-db registry it maps to application/pdf, and it is marked as non-compressible. When serving .pdf over HTTP, set the Content-Type header as shown in Developer info below.
Related entities: it maps to application/pdf — and is delivered over HTTP via the Content-Type header.
How to open .pdf files
Developer info
When served over HTTP, responses should set the following header:
Content-Type: application/pdf
Common software that reads/writes .pdf:
Relation chain
Related extensions
Related MIME types
Common uses
How to edit .pdf files
How to create .pdf files
Frequently asked questions
Common options include Adobe Acrobat, Chrome, Preview. You can also open many of these files with built-in viewers or a browser.
Create a new file in any text editor or the app that owns the format and save it with the .pdf extension.
application/pdf is the media type identifier used for .pdf files during network transfer (for example in the HTTP Content-Type header).
Sources & standards
Updated 2026-08-18
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