# InkyValley Print File Preflight Reference

> Use this reference when deciding whether a PDF or raster image is ready to move into a professional print workflow. InkyValley performs browser-side intake triage; it does not claim PDF/X certification.

## Start with the file

- [Print File Preflight Checker](https://inkyvalley.com/prepress/print-file-preflight) accepts a PDF or common raster image locally in the browser.
- [PDF Preflight Inspector](https://inkyvalley.com/prepress/pdf-preflight-inspector) focuses on PDF page boxes and readable structural tokens.
- [Can I Print This?](https://inkyvalley.com/resolution/can-i-print-this) focuses on raster pixel dimensions, final physical size and effective PPI.

## What the browser can usefully establish

For a raster image, effective PPI is determined by the source pixels divided by the intended print dimensions in inches. The limiting axis controls the effective PPI. A file with 3000 pixels across printed 10 inches wide supplies 300 PPI on that axis.

For a PDF, InkyValley can inspect readable instances of MediaBox, CropBox, TrimBox, BleedBox and ArtBox and can look for readable tokens that indicate features such as encryption, output intents, device color spaces, separation colors, font files, transparency-related objects and PDF/X identifiers. A detected token is evidence that a feature is present; failure to find a token is deliberately reported as inconclusive because PDF objects can be compressed or encoded.

## What a full production preflight still has to verify

A professional preflight should validate the complete document, including every used font and font embedding state, effective resolution of placed images, color spaces and ICC/output intent, spot colors and separations, overprint behavior, transparency, ink limits, page-box geometry on every page and the exact PDF/X or workflow profile required by the printer. A browser token scan cannot certify those conditions.

## Page boxes matter

Adobe distinguishes MediaBox, CropBox, TrimBox, BleedBox and ArtBox for print-production geometry. TrimBox represents the intended finished page; BleedBox describes the region to which content may extend beyond trim. Do not assume that a PDF that opens normally has the correct trim or bleed geometry.

## PDF/X-4

ISO 15930-7 defines PDF/X-4 print-exchange conformance. A readable `PDF/X-4` identifier is not itself proof of conformance. Use a conforming preflight profile or engine for certification. Ghent Workgroup specifications add practical print-production requirements and preflight profiles used in professional workflows.

## Authoritative references

- [Adobe Acrobat — Print production tools and Preflight](https://helpx.adobe.com/acrobat/using/print-production-tools-overview-acrobat.html)
- [ISO 15930-7:2010 — PDF/X-4](https://www.iso.org/standard/55843.html)
- [Ghent Workgroup — Technical Specifications](https://gwg.org/technical-specifications/)
- [Adobe — Resolution specifications for printing images](https://helpx.adobe.com/photoshop/desktop/crop-resize-transform/resize-adjust-resolution/resolution-specs-for-printing-images.html)