Blog  /  Gerber Files: A Step by Step Guide on How to Generate Gerber Files 

Gerber Files: A Step by Step Guide on How to Generate Gerber Files 

Printed circuit boards (PCBs) have been in existence for almost a century. This demonstrates their relevance in electronic circuit systems. For this reason, the demand for small and high-density PCBs is increasing yearly in the digital era. Nowadays, creating the smallest circuit board sizes is facilitated by the use of cutting-edge manufacturing technologies. While PCB manufacturing consists of different dimensions, tools, and materials, it heavily relies on Gerber files.

So, what are Gerber files? How do you generate Gerber files? This article contains the answers to these questions and other features of Gerber files.

Welcome to the step by step guide on how to generate Gerber files.


1. The Definition of a Gerber File


As mentioned earlier, a Gerber file is one of the essential elements of PCB design. The name originates from Gerber Systems Corp- the first company to develop Gerber files. It refers to the PCB features, like solder mask layers, legend, drill template, etc.

Typically, you will design your PCB in CAD systems that use manufacturing information to produce two or three-dimensional circuit board designs. Likewise, you need to enter data into these systems to create the designs. Does this sound simple? I know you may think it is a system that automatically makes designs upon entering the data.

However, that is not true as you have to refer to Gerber file guidelines while keying in the information. Gerber files define the requirements in every product development step. Remember, you can use these files for circuit board fabrication and assembly.


A Gerber file adheres to the basic ASCII vector setup, and it contains the following features:


  • Configuration factors
  • Macro and aperture measurements
  • Draw and flash command codes
  • XY Coordinate settings.

Again, there is a Gerber file for every drill span and image layer of the PCB found in a single template. Sometimes, you can send over eight documents for a two-layered board to your PCB manufacturer. They may comprise:

  • A picture of the copper layer to be placed on the lower part of the board.
  • A picture of the copper layer to be placed on the upper part of the board.

There would be two templates for the solder mask and silkscreen pictures for your manufacturer to include on the circuit board's lower and upper parts. Besides, there will be templates containing different drill holes, their position, and use.

Mostly, surface riding and overlaid holes come in various templates. A comprehensive PCB information outlines multiple procedures, such as machining processes that you should carry out and others.


2. How to Make PCB Gerber Files


First, you can barely ensure that your manufacturer uses the same software you used in the design process.

In case your manufacturer specifies that they are using different software, you should make Gerber files by yourself. Further negotiations and requests will consume your time and affect the manufacturing process significantly.

Still, even if both of you use the same design software, generating Gerber files by yourself is crucial in preventing possible errors resulting from different terms.

Hence, to ensure the production process proceeds as planned and your end products are reliable, you should learn to make Gerber files independently. Generally, Gerber files come with design information of conductor, solder mask, and silkscreen layers. Additionally, regarding the two layers containing similar design information, you should still generate your Gerber files one by one to avoid any mix-up.

It is essential to realize that various PCB design tools have distinct operations steps of Gerber file creation. We will discuss how to generate Gerber files using Kicad, Altium Designer, and Eagle software.


2.1 Kicad- Kicad Exporter Gerber


Generally, it is much easier to create Gerber files via Kicad than other circuit board design tools. What you need to do is to choose the appropriate layers and make the DRILL file. Without further ado, let us dive into the process of generating Gebers in Kicad!


Open your .kicad_pcb file


First, open your Kicad project. Then, double click the .kicad_pcb template. Alternatively, you can press the "PCBNew" tab to open the circuit board editor.


Plot your Kicad PCB as Gerber Files


On your File menu, proceed to the Plot function and select the appropriate layers, as illustrated in the diagram below. Likewise, press the Plot tab to produce the corresponding layers.

Gerber Files

The essential layers you need for a 2-layer circuit board are:

  • The upper layer- pcbname.GTL
  • The bottom layer- pcbname.GBL
  • The solder mask upper layer- pcbname.GTS
  • The solder masks the lower layer- pcbname.GBS
  • The upper silk layer- pcbname.GTO
  • The silk lower layer- pcbname.GBO
  • The drill drawing layer- pcbname.TXT
  • The board outline layer- pcbname.GML/GKO


Generate the Drill


Another critical point to note is that you should create the drill for manufacturing purposes before closing your plot panel. With this in mind, tick the Suppress leading zones and Minimal header boxes. Then press the Drill File tab, as illustrated below.


Generate the Drill


That is it. You are done with generating Gerber files!


Check the Gerber Files in Gerber View


Though you have finished generating Gerber files, you should confirm whether they are correctly functioning before folding your tools.

Luckily, the process of checking Gerber files is as simple as ABCD. Click the GerbView and confirm the shape and configuration of your PCB. If everything is OK, you can now send your Gerber file to your PCB manufacturer.


Your board should resemble the image below.


Check the Gerber Files in Gerber View


Compress your Files in a Single .zip File


Lastly, you should compress your files in one .zip file. Besides, you should fill out the document about your board features, such as size.

You can check this video for a comprehensive illustration of how to export Gerber files in Kicad


2.2 Altium Designer- Altium Gerber Files


The first thing you should do is to introduce a new OutJob template to your circuit board project. Upon adding the file, you can think of the manufacturing documents you need to create and its formats.

As an illustration of these points, you can refer to the diagram below. It is a demonstration of several alternatives powered for various manufacturing documents. Note that we have chosen Gerber RS-274X documents and specifications for all back drilled layers.

If you want to generate a new export alternative for Gerber X2 templates, right-click the Fabrication Outputs button and choose the Gerber X2 item.





Remember that you can generate different sets of Gerber Outputs. For the diagram above, the Backdrill Gerbers and the Gerber Files items are located on the RS-274X documents. However, they will produce Gerber files for different layers.


After creating a new Gerber Output alternative


You should configure the data you will export with these options.

The diagram below illustrates the dialog that will help you choose units, template format, and export layers. To use the conference, right-click one of your Gerber file items and press Configure.





The above diagram illustrates the dialog you will get for the RS-274X document. Nevertheless, you will find the same discussion if you use the X2 form. It is important to note that the conference contains two primary buttons:

  • The Layers Tab. You can maneuver through the Layers Tab, able to choose your preferred layers for export. They include electrical, mechanical, and silkscreen layers.
  • The Drill Drawing Tab. If you had this button to choose the matching drill layers, you would adapt to a Gerber template. Naturally, this tab contains a top and bottom layer. But if you have powered any other Viator drill element, such as blind Vias, you will access their corresponding options.

In the diagram below, we have enabled all the Gerber templates and other manufacturing documents you should export. To complete this process, hit the Generate Content button on the right side of your workspace.





Wow, you have successfully generated your Gerber files. As a professional, check your Gerber files to ensure there are working correctly. Remember, even simple issues can result in an unsuccessful fabrication run.

You can watch the video below to have a visual illustration generating Gerber files in Altium Designer.


2.3 Eagle- Eagle Gerber Files


The critical point you should bear in mind in Eagle Gerber files is that it is impossible to use Eagle templates for circuit board manufacturing. Therefore, you should export your Gerber templates directly to a circuit board fabrication. In this section, you will learn how to send Gerber documents from the Eagle .brd file to your PCB manufacturer.

Before creating Gerber files, the first thing to remember is to check whether the silkscreen lies on a single or double side. This is because, by default, you will only generate the upper silkscreen layer.

Therefore, if your circuit board contains a two-sided silkscreen, you should also introduce the lower layer. If your .brd file has milling designs, ensure you incorporate an additional outline layer before ticking the Miling Dimension.

Now, follow these steps to generate Gerber files for your PCB manufacturing.


Generate Drill Files


Running the drilling command is the first step in generating Gerber files in Eagle.

To achieve this, navigate to the File section and click Run ULP. Press OK on the pop-up that appears to create the conforming drill configuration template.


Generate Drill Files




Next, open the .brd document and scroll down the File section to open the CAM Processor.

Within the CAM processor, navigate to the File tab and click Open access the Open CAM Job. After that, press the Open tab in the excellent one. Cam dialog box.

Then, press the Process Job tab to create the conforming drill file.


Generate Drill Files




Generate Gerber Files


Remember, we are still in the CAM Processor dialog panel. Now proceed to the File section, select Open and click the Job button to access the Open CAM Job command. Then hit the Open tab in the gerb274x. Cam section. When it is ready, press the Process Job button to create the matching Gerber template.


Generate Drill Files



After that, go the panel labeled Add to modify these parameters: Change Section to Silkscreen b1, and File to %N.pls. Additionally, discard the layers to remain with layers 20 Dimension, 22 places, and 26 blames.

Remember to include an additional layer before selecting the 20 Dimension and 46 Milling if you encounter a milling design.

Now, before sending your Gerber files to your PCB manufacturer, confirm that the layers are OK.


Compress your files in a .zip File


The last step is compressing your files into one .zip file. Remember to fill out the circuit board document parameters before sending your Gerber file to your manufacturer.

For a visual illustration of exporting Gerber files in Eagle, check out this link.

Eagle has made it easier for users to generate Gerber files in version 9.6.2. You only need to click the Process Job button to have your Gerber files.


3. The Importance of Gerber Files in PCB Manufacturing


Gerber files have increased their functionality to include more configuration data and macro and aperture descriptions. The laser plotters PCB manufacturers rely on today still utilize the same Gerber data. However, the aperture limitations of the earlier vector plotters are no longer applicable.

The plotters change the Gerber parameters to a raster document, as the data directs the plotter on how, where, and what to generate. While the Gerber file sector is continuously evolving, they will continue to hang on their current state for a while before undergoing significant changes.


4. PCB Gerber Standard File Extension


4.PCB Gerber Standard File Extension



5. How to Open GBX Files


There are five simple steps of opening a GBX file:

First, double-click the GBX file icon. If it fails to open or an error message pops-up, proceed to the next step.

Secondly, select the appropriate program. If your file failed to open in step one, it means your computer is lacking some basic GBX programs. Download some GBX programs to sort out the issue.

Thirdly, figure out your file types.

Next, get in touch with your developer if you are still experiencing problems opening your GBX template.

Lastly, install a universal file viewer if the problem persists. You can still use it to open numerous types of files.




As a PCB designer or a fabrication engineer, you should master circuit board manufacturing requirements to generate Gerber files properly. Some manufacturers request for two aperture lists and additional data templates. Therefore, you should understand the role of those templates and how to generate them.

While most PCB processes are automated nowadays, it is still essential to understand the Gerber file generation process and the whole PCB design process.