What is a C4 file?
A .C4 file is a black-and-white raster engineering drawing format associated with JEDMICS. It is common in defense logistics, DIBBS solicitations, and archived technical drawing workflows.
The short version
C4 stores line-art drawings using CCITT Group 4 compression, the same compression family used for black-and-white fax images. That makes C4 files compact and accurate for scanned engineering drawings, but not easy to open in normal image viewers.
- Used byJEDMICS and related defense drawing repositories.
- Best forMonochrome technical drawings, schematics, and scanned line art.
- Open asPDF for sharing, TIFF for archival workflows, PNG for embedding, or JPEG for small previews.
Where C4 files show up
Contractors usually encounter C4 drawings as technical attachments from defense procurement or engineering data systems. Common source systems include DIBBS, NSEDR, NATEC, AVPLM, and DLA Land and Maritime drawing packages.
C4File.com is built for that workflow: open the drawing in the browser, inspect it, then export a standard format without sending the drawing to a server.