Local print file forensics
See what the file actually contains.
Inspect the file structure before trusting a DPI label, filename or export preset. Print Prep Lab reads supported metadata in your browser and never uploads the selected image.
v27 · Local file forensics
Inspect the file before the print math
Read structure and metadata locally. Density tags are reported as metadata—not mistaken for effective print PPI.
What this can revealReal dimensionsPixel width, height, megapixels and aspect ratio.
Density metadataJFIF/EXIF or PNG pHYs tags, clearly separated from effective PPI.
Color signalsEmbedded ICC/sRGB indicators when the file structure exposes them.
Integrity identitySHA-256 lets you prove whether two delivery files are byte-for-byte identical.
Reading the evidenceMetadata can describe a file without deciding how large it should print.
The inspector separates structural facts—pixels, chunks, profiles, checksums—from print decisions that depend on final physical size.
A 300 DPI tag is not the same as 300 effective PPI
JPEG JFIF/EXIF density values and PNG pHYs values can store an intended physical scale. Changing that metadata can change how some software initially places the image, but it does not create new pixels. Effective print PPI still comes from usable source pixels divided by the final printed inches after crop or fit.
That is why the inspector reports density metadata as a separate field and adds a warning instead of using it as a readiness verdict.
ICC and sRGB signals need workflow context
An embedded ICC profile is useful because it describes how encoded color values should be interpreted. The lightweight browser parser can identify supported ICC or sRGB structures, but it does not replace a color-managed prepress application, soft proof, printer profile or physical proof.
Likewise, failing to detect a profile signal does not prove the file is unusable. Some workflows assign a profile externally or use file structures this lightweight parser does not fully decode. Confirm the provider's requested color workflow.
SHA-256 identifies the exact bytes you selected
A SHA-256 checksum is useful when filenames are unreliable. Two files with the same cryptographic hash are, for practical delivery purposes, the same byte sequence. A renamed duplicate therefore remains detectable.
The checksum says nothing about whether the image is sharp, correctly cropped or color-managed. Use it for identity and delivery control, then use Studio, Preflight and the provider specification for print decisions.