Does my PDF get uploaded anywhere?
No. All inspection runs in your browser using PDF.js (the same open-source library Firefox uses to display PDFs). Your file never leaves your computer. We don't see it, we don't store it, and we don't transmit it. Confidential architectural drawings, NDA'd projects, and client documents are safe to inspect.
What does the diagnostic actually measure?
Seven specific properties: (1) source application from the PDF's Producer/Creator metadata — typically tells us if the file came from ArchiCAD, Revit, AutoCAD, Vectorworks, SketchUp, or office software; (2) file size; (3) page count; (4) paper size (A4, A1, ANSI D, etc.) from the first page's bounding box; (5) vector density — we count drawing operations on a sample of pages and extrapolate; (6) embedded raster images; (7) layer metadata (Optional Content Groups in the PDF spec). Each property gets a 'Light / Standard / Heavy' rating based on where general-purpose viewers measurably slow down.
Why does this matter for choosing a PDF viewer?
PDFs from CAD software are fundamentally different from PDFs of contracts, reports, or invoices. A 5 MB contract PDF and a 5 MB site plan look the same to the file system, but a viewer's rendering load is wildly different — the site plan can contain 50× more vector operations on a single page. General-purpose viewers like Adobe Acrobat are optimized for document workflows (forms, signatures, prepress) and trade off raw vector rendering speed. Ncored is built specifically for the vector-dense AEC export case.
Why is some of the analysis a sample, not exact?
Counting every vector operation in a 200-page drawing set would take 30+ seconds in the browser. The diagnostic samples the first one to three pages and extrapolates — this gives a reliable estimate of per-page complexity without making you wait. The metadata properties (source app, paper size, file size, page count, layers, encryption) are read directly from the PDF and are exact.
What if the source app isn't detected?
Many PDFs go through a generic print-to-PDF driver (Microsoft Print to PDF, Adobe PDF Library, macOS Quartz PDFContext) which obscures the original authoring application. The source detection looks for ArchiCAD, Revit, AutoCAD, Vectorworks, SketchUp, Bluebeam, and common office apps in both the Producer and Creator metadata fields. If none match, the report says 'Source not detected' — this isn't a problem; the other properties still give us enough to characterize the file.
Where can I download Ncored?
Ncored is available for macOS (native Apple Silicon, no Rosetta) and Windows. Free 14-day full-feature trial, no credit card required. Download from the main page.