Useful tools.
Private files.

What we make

Local file tools convert, inspect and organize images and PDFs without a server upload. Production calculators answer specific questions such as whether an image is large enough, how labels fit on a sheet or how a book cover spread is estimated.

Editorial standard

We publish the method, a worked example and practical limitations alongside every tool. Tools are manually tested against known examples before release. Where a printer, carrier or platform controls the final specification, we say so clearly.

Privacy by design

Calculations and file processing run locally in your browser. File Preflight does not require an account and does not receive the files or values you select. Optional analytics records page views and tool actions—not filenames, artwork or calculator inputs.

Corrections

If you find a formula, preset or explanation that should be corrected, contact the editorial team at hello@filepreflight.com. Include the tool name, your test inputs and the source specification when possible.