Overview

application/pdf is the media type for Portable Document Format documents, created by Adobe and standardized as ISO 32000. It reproduces layout, fonts, images, and vector graphics identically across devices and is the de facto standard for print, contracts, and reports.

Details

Browsers receiving application/pdf render it inline in a built-in PDF viewer by default. To force a download send `Content-Disposition: attachment; filename="invoice.pdf"`, or use `inline` to make inline display explicit. For large PDFs, supporting `Accept-Ranges: bytes` and range requests lets a viewer fetch the first page and display progressively (a linearized / fast web view).

PDF can contain JavaScript, forms, attachments, and external links, making it an active-content container. Opening an untrusted PDF exposes the viewer's attack surface. Servers should validate the file signature (files start with `%PDF-`) to reject disguised uploads.

Syntax

e.g. Content-Type: application/pdf

File extensions

Notes

• For non-ASCII filenames, include the RFC 5987 `filename*=UTF-8''...` encoding alongside the plain filename.
• In-PDF JavaScript and auto-run actions can be a malware vector; viewer sandboxing and up-to-date patches matter.
• When streaming dynamically generated PDFs, an incorrect Content-Length (without chunked transfer) can make viewers treat the file as truncated.

Related types

Related headers