What is JEDMICS?
A definitional reference for the Joint Engineering Data Management Information and Control System. Primary source: jedmics.net, the U.S. Navy-registered JEDMICS program site operated from NAS Patuxent River, Maryland.
Overview
JEDMICS, the Joint Engineering Data Management Information and Control System, is a U.S. Department of Defense repository that stores unclassified engineering and related technical data. Its primary artifact is the .C4 file: a compact black-and-white raster image of an engineering drawing, compressed with CCITT Group 4 facsimile encoding.
Historically, JEDMICS has been the principal channel through which contractors and DoD personnel have exchanged engineering drawings with the armed services. As of the mid-2020s, two of the largest services, Naval Air Systems Command (NAVAIR) and the Department of the Air Force, have transitioned to successor systems (AvPLM and A-TEAM respectively). Many .C4 files from prior solicitations and archives remain in circulation, and still need to be opened.
Purpose and supported work
The official JEDMICS program site describes the system's purpose directly:
“JEDMICS is a repository that stores unclassified engineering and related technical data. JEDMICS supports multiple disciplines that include material management, maintenance repair and depot level overhaul, engineering, acquisition, and sustainment efforts.” jedmics.net
In practice this means JEDMICS-stored drawings and technical data are used across the full life-cycle of DoD equipment: from initial acquisition and design review, through sustainment and depot-level overhaul, to end-of-life material management.
Current program status, 2025 to 2026
The JEDMICS program has been in an active transition. Two announcements published on jedmics.net define the current state:
Holders of historical .C4 files, from archived DIBBS solicitations, contractor deliverables, or prior repository exports, still need a viewer to open them. For that purpose, see c4file.com.
The .C4 file format
A .C4 file is a single-page or multi-page raster image designed for engineering drawings. Inside the file, the image data is compressed using CCITT Group 4, the same compression used by black-and-white fax machines, standardized in ITU-T Recommendation T.6.
The format was chosen for a specific case: line-art drawings where the image is mostly white paper with sharp black linework, tables, and annotations. For that case, CCITT G4 is extremely efficient. A 34×44-inch scanned engineering drawing typically fits in a few hundred kilobytes, far smaller than a general-purpose raster or PDF would produce.
The trade-off is that .C4 is a narrowly-scoped format. General-purpose image viewers (such as macOS Preview or Windows Photos) usually cannot open .C4 files directly without a dedicated decoder.
Official specifications
The authoritative JEDMICS specifications are published on the program's public specs page:
| Specifications index | jedmics.net/public/open-specs.html |
|---|---|
| C4 Image Specifications | Last updated 15 April 2002. Defines the .C4 wrapper around CCITT Group 4 data. |
| TDP Import Format | JEDMICS Technical Data Package import specification (PDF and Excel). |
| JBR 3.0.22 RST / DFIS | Format definitions document (PDF). |
| CDEX DLF Format | The Compact Disk Exchange / Data Loadable Format is noted as obsolete on the official specs page. |
The underlying compression is defined by ITU-T Recommendation T.6, the international standard for CCITT Group 4 facsimile encoding.
Who runs the official site
The official JEDMICS program site, jedmics.net, is registered in the United States and hosts only program-planning information. It does not store drawings or manage JEDMICS accounts. Per the site itself:
“This web site does not store drawings nor does it provide access to drawings or manage accounts for JEDMICS systems.” jedmics.net
Public WHOIS records list the registrant address as Building 416, Room 100A, at Patuxent River, Maryland: the location of Naval Air Station Patuxent River, which hosts NAVAIR and related commands. A warning banner on the site identifies the hosting infrastructure as part of the Peraton computer network. Peraton is a federal IT services contractor.
This site (jedmics.com) has no connection to that registration. It is operated independently by Secureframe, a private U.S. cybersecurity company, as a public informational reference.