PDFX3

PDF/X-3 is a subset of the Portable Document Format designed for the exchange of graphic arts and prepress materials in the printing industry. It belongs to the PDF/X family of ISO standards (ISO 15930) and aims to ensure reliable, predictable output by constraining features that can affect reproduction. PDF/X-3 emphasizes color management by allowing ICC profiles and color-managed workflows.

Key requirements include embedded fonts, well-defined color spaces, and explicit rendering instructions. The standard supports ICC-based color management to achieve consistent color across devices, while maintaining the general portability and self-containment of PDFs used in printing. It allows both CMYK and RGB workflows, provided color information is unambiguous.

PDF/X-3 was introduced as a counterpart to PDF/X-1a and represents an early effort to combine device independence with modern color workflows. Compared with later variants such as PDF/X-4, it is considered older and less feature-rich, but remains in use where ICC-based color handling is essential and compatibility with older tooling is required.

In practice, files intended for PDF/X-3 conformance are validated with preflight or conformance checks before submission to printers. The standard is commonly used for professional printing projects where accurate color reproduction is critical, and it remains part of the broader ecosystem of prepress data exchange.