How to generate the Gerber (manufacturing) files?

To place an order on Seeed Fusion service, you need to provide us with the necessary manufacturing files to produce your consignment. For Printed Circuit Board manufacture, we require the Gerber files in RS-274x format and a drill file in Excellon format. For your convenience, we have written guides on how to generate the necessary files in the correct format in some of the most popular circuit design programs available.

Altium Designer








The guides apply to four layer boards or less, for additional layers, please ensure that you export the necessary circuit layers.

For PCB orders, the following manufacturing files should be supplied together in a single .rar or .zip archive file. To import correctly into the Online Gerber Viewer, and to help us identify the layers, please manually change the extensions of your generated files to the ones listed below. If we cannot identify the layers we may contact you for confirmation.

      Extension                                 Layer
  • pcbname.GTL                Top Copper 
  • pcbname.GTS                Top Soldermask
  • pcbname.GTO               Top Silkscreen
  • pcbname.GBL                Bottom copper
  • pcbname.GBS                Bottom Soldermask:
  • pcbname.GBO               Bottom Silkscreen:
  • pcbname.TXT/DRL        Drills
  • pcbname.GML/GKO      Board Outline
  • pcbname.GL2                Inner Layer 2 (for ≥4 layers)
  • pcbname.GL3                Inner Layer 3 (for ≥4 layers)


- There must be a complete board outline in your files to show us how to cut out your boards. Ideally, this should be included in the mechanical layer and not only in the silkscreen layer. In some design software, you may be required to draw this yourself manually.

Do not use non-ASCII characters in any file or folder names, this will prevent the files from importing into our CAM software..

Having problems generating the drill layer in Excellon format? If your design software does not have the option to generate the drill file in Excellon format, you can download CAM350 for free and convert it. For more information, click here.

For more information on how to place a PCB order, click here.

For information on the files required for Stencils, click here.

Fusion Technical Support

  1. What is Gerber file?
  2. What are the PCB panelization rules?
  3. How to generate the Gerber (manufacturing) files?
  4. What is the correct way to draw the silkscreen on the bottom side?
  5. My PCB does not require Solder Mask, what should I do?
  6. My PCB does not require Drill Holes, what should i do ?
  7. Which layer should I use in EAGLE for milling?
  8. What is the depth and width of the v-cuts/grooves?
  9. I don't want silkscreen on my PCBs, how can I proceed with a PCB Assembly order?
  10. What are the dimensions for Dielectric Separation thickness?
  11. What is the thickness of the inner copper layers?
  12. What are Blind and Buried Vias?
  13. What is the The Min Track/Spacing for 1oz./2oz./3oz. Copper weight
  14. What are Plated Half-Holes/Castellated Holes?
  15. How do I design non-plated through holes/slots?
  16. What PCB materials are available in Seeed Fusion?
  17. What is the thickness of Fusion PCB?
  18. What PCB surface finishes are offered in Seeed Fusion?
  19. What color options are available for the solder mask/resist?
  20. What is the PCB copper weight?
  21. What is Impedance Control?
  22. PCB quantity
  23. How do plated through holes/slots shows on the Gerber?
  24. How to generate Gerber files from PCBE
  25. How to generate Gerber files in Altium Designer
  26. How to generate Gerber files from CircuitMaker
  27. How to generate Gerber and Drill files from Eagle
  28. How to generate Gerber and drill files from KiCad
  29. How to generate Gerber files from DipTrace
  30. How to generate Gerber files from Proteus
  31. How to generate Gerber files from DesignSpark
  32. How to convert drilling layer from Gerber to Excellon format in CAM350
  33. Recommend size for BGA
  34. Solder Mask Dam
  35. What is the difference between Fusion standard PCB and Fusion Advanced PCB?
  36. What should I do if my Gerber files are too big (over 4MB)?

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