Gerber, ODB++, and IPC-2581 are three PCB manufacturing handoff formats with different strengths. Gerber is the widely supported image-based format used by nearly every board house. ODB++ is a richer structured job package controlled by its vendor ecosystem. IPC-2581 is an open, vendor-neutral XML-based standard designed to carry richer board data in one file.
The choice is not only technical. It depends on what your PCB tool can export, what your manufacturer can import, and how much manufacturing intelligence you need in the handoff. A simple two-layer prototype may be handled perfectly with Gerber X2 and Excellon drills. A complex board with stackup, netlist, assembly, and DFM automation needs may benefit from ODB++ or IPC-2581 if the receiving fab supports it.
For the normal file list around a Gerber order, see what files to send to a PCB manufacturer. For the modern Gerber attribute model, read what Gerber X2 is.
Quick answer
Gerber is an open, Ucamco-maintained, per-layer PCB image format and the de-facto universal default. ODB++ is a proprietary rich job package, usually delivered as an archive or directory. IPC-2581 is an open XML-based single-file standard for richer PCB manufacturing data. Use the format your manufacturer supports.
Gerber: broad support and simple layer images
Gerber files describe PCB layer images. A fabrication release normally contains one Gerber per copper, mask, silk, paste, outline, or other manufacturing image. Modern Gerber means RS-274X or Gerber X2. RS-274X embeds apertures and format settings in the file. X2 adds attributes that can identify layer function, apertures, pads, vias, nets, and component-related objects.
Gerber is open and maintained by Ucamco. Its greatest practical strength is support breadth. Nearly every PCB manufacturer can accept a correct Gerber package. The tradeoff is that Gerber is fundamentally a per-layer 2D image format. A complete order normally includes separate drill data as well — commonly Excellon drill files, unless your fab accepts Gerber/XNC drill data — plus stackup notes, fabrication notes, BOM, and pick-and-place files when those are relevant.
Gerber X2 reduces ambiguity, but it does not make Gerber a full design database. The manufacturer still receives a set of files, and filenames, layer maps, drill files, and notes still matter.
ODB++: rich proprietary job package
ODB++ is a structured PCB manufacturing database that originated with Valor and is now associated with Siemens/Mentor. Instead of sending one image file per layer plus separate support files, ODB++ packages many kinds of job data together. It can include layer images, drill data, netlist information, component data, stackup information, and other CAM context depending on the exporter and receiving workflow.
In practice, ODB++ is usually delivered as a compressed archive or as a directory structure. People often call it a single-package format because the job is transferred as one organized package, even though the package itself contains multiple internal files and folders. Its strength is that it can carry more intent and reduce manual interpretation. Its limitation is that it is proprietary and vendor-controlled, so support depends on the tools and licensing around both the sender and receiver.
IPC-2581: open XML-based rich exchange
IPC-2581 is an open, vendor-neutral standard for PCB manufacturing and assembly data exchange. It is XML-based and designed to carry a broad set of information in a single file, including image data, drill data, netlist, stackup, materials, component information, and assembly-related data when exported.
IPC-2581 is often described as an open alternative to ODB++ because it targets the same problem: reducing ambiguity by moving more manufacturing intent into one intelligent handoff. Its challenge is support breadth. It has grown across EDA and manufacturing workflows, but it is not as universally expected as Gerber. Before using it as the primary handoff, confirm that the fab can import the specific IPC-2581 output from your tool.
Format comparison
| Format | Open or proprietary | Package style | Included data | Support breadth |
|---|---|---|---|---|
| Gerber RS-274X / X2 | Open, maintained by Ucamco. | Multiple per-layer files, usually ZIPped with drills. | 2D layer images; X2 can add attributes. Drills separate. | Very broad, common default for PCB fabs. |
| ODB++ | Proprietary, vendor-controlled format. | Single job package as archive or directory. | Can bundle image, drill, netlist, stackup, and components. | Strong in supported CAM flows, but not universal. |
| IPC-2581 | Open, vendor-neutral industry standard. | Single XML-based file. | Can include image, drill, stackup, netlist, and components. | Growing support, but verify with the manufacturer. |
Which format should you send?
If you do not have a specific requirement, Gerber X2 or RS-274X plus Excellon drill files is usually the safest default because of broad manufacturer support. It is simple, inspectable, and accepted by a very wide range of prototype and production fabs. Include a clear layer map, stackup notes, and any special fabrication requirements to avoid ambiguity.
Use ODB++ when your EDA tool exports it well, your manufacturer requests it or supports it confidently, and you want a richer CAM package with more job intelligence. Use IPC-2581 when you want a richer exchange format but prefer an open standard and your fabrication or assembly partner can process it. For critical jobs, ask the manufacturer which format their CAM team prefers rather than assuming the richest format is automatically the safest.
See Gerber output in the viewer
Even if you also send ODB++ or IPC-2581, many teams export Gerbers for visual review because the layer images are easy to inspect. Open the Gerber ZIP in the Gerber viewer and confirm that copper, mask, silk, paste, outline, and drill data match your expectations. If the exported images do not match the design, regenerate the manufacturing package before sending any format to the fab.
FAQ
- Is Gerber still the safest default for PCB fabrication?
- For broad manufacturer compatibility, Gerber RS-274X or Gerber X2 plus Excellon drill files is usually the safest default unless your fab requests another format.
- Is ODB++ a single file?
- ODB++ is a structured job package, commonly delivered as a compressed archive or directory. It bundles many kinds of manufacturing data into one package.
- Is IPC-2581 open?
- Yes. IPC-2581 is an open, vendor-neutral XML-based standard intended to carry rich PCB manufacturing and assembly data in a single file.
- Do ODB++ or IPC-2581 remove the need to check files?
- No. Richer formats reduce some ambiguity, but you should still verify the exported package, confirm manufacturer support, and follow the fab instructions.