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PCB design glossary

Drill File

AKA: excellon, drill data

A file (usually Excellon format) that tells the fab where to drill holes — for vias and through-hole pads.

Drill files (Excellon: .drl, .exc, .xln) describe every hole that needs to be drilled into the PCB: position, diameter, plated or non-plated. They ship alongside the Gerber files in the fab package.

Drill data and Gerber artwork together describe the entire board. Drill is its own file (not part of a Gerber layer) because the drilling step happens with different machinery from the photolithography that defines copper.

Designing a board that uses drill file?

PCBEditor turns a plain-English description into a verified schematic — then handles placement, routing, and export to Gerber or KiCad.

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