I am generating gerber files for manufacturing of my PCB. I have completed my PCB layout.

When generating gerber files/ drill files I am getting several options. What are they? I have highlighted the options in below image in red boxes. See below image:

enter image description here

I would appreciate answers explaining any/some/all of the above options (highlighted in 4 red boxes). Let me know if any more clarification is needed. I am using KiCAD.

  • 1
    \$\begingroup\$ Your manufacturer may be able to tell you which options they prefer if you send them this screenshot. \$\endgroup\$ – Justin Aug 28 at 19:42
  • \$\begingroup\$ Always check with your board fab. for their requirements. OSHPark for instance, wants "PTH and NPTH drills in a single file" enabled. I also place the origin point on the board corner and enable "Drill Origin: Auxiliary Axis." If your fab has a preview capability, use it to ensure they can read your gerber data correctly. \$\endgroup\$ – rdtsc Aug 31 at 12:22


Excellon format contains the drill coordinates and the diameters of the drills. Almost all manufacturers prefer this format because it's a kinda industry standard. I've never seen a PCB manufacturer requesting the drill files in Gerber-X2 format.


  • Mirroring: Mirroring the data along the Y-axis may not be the thing you "have to" do. If a manufacturer prefers drilling the holes from the backside then they can mirror the data.

  • Minimal Header: I don't know what Minimal Header refers to and what it is used for.

  • Merging PTH and NPTH drills in a single file: There are two types of holes: PTH (plated through-hole, which indicates a drill with through-hole conductive plating) and NPTH (non-plated through-hole, which indicates a standard drill with no plating). Generating separate files for PTH and NPTH drills is useful when cross-checking the final gerbers coming from the manufacturer to confirm before production. I always generate separate PTH and NPTH drill files.


The point where all the drill coordinates are referenced to.

  • Absolute origin: This indicates that the origin is the global (x=0,y=0) coordinate. I always prefer the global origin coordinate to be the origin for both gerber (mostly RS-274X) and the drill files.
  • Auxiliary Axis: I've never used KiCad, so I'm not sure. But I think that this option allows the designer to manually select a point to be the drill origin. You may not need this.


A drill map is a 2D drawing which contains all the drills marked with individual symbols, and a table showing which symbol indicates which type of drill (i.e. diameter, type, etc). It can be useful for cross-checking each drill, but mostly it's not required. The drill files are enough. Following is an example to a drill map (The manufacturers can generate this from the data files you send):

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