RS-274X (Extended Gerber)

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What is Gerber?

Gerber is a 2D vector image file format that describes the layout of a PCB. It contains information about the copper traces, solder mask, silkscreen, and other features of the board. Gerber files are used by PCB Manufacturers to create the physical boards based on the designer’s specifications.

The original Gerber format, known as RS-274D, was limited in its capabilities and could not handle the increasing complexity of modern PCB designs. In 1998, the RS-274X format was introduced to address these limitations and provide a more robust and flexible solution for PCB design and manufacturing.

Features of RS-274X

RS-274X introduces several new features and enhancements to the original Gerber format, including:

Aperture Macros

Aperture macros allow the definition of complex shapes and patterns that can be reused throughout the design. This feature reduces file size and improves efficiency by eliminating the need to define the same shape multiple times.

Polarity Control

RS-274X introduces the concept of polarity for apertures and draws. This allows the designer to specify whether an area should be filled or unfilled, making it easier to create complex shapes and patterns.


The Extended Gerber format supports various interpolation modes, including linear, circular, and arc interpolation. This allows for the creation of smooth curves and arcs, which are essential for modern PCB designs.

Nested Apertures

RS-274X allows for the nesting of apertures, which means that one aperture can contain another aperture within it. This feature enables the creation of complex shapes and patterns that would be difficult or impossible to achieve with the original Gerber format.


Attributes can be assigned to apertures, draws, and other elements in the design. These attributes can include information such as the function of a particular feature, the layer it belongs to, or any other relevant data. Attributes help to make the design more organized and easier to understand.

Advantages of Using RS-274X

Using the Extended Gerber format offers several advantages for PCB designers and manufacturers:

  1. Improved accuracy: RS-274X allows for the creation of more precise and detailed PCB layouts, reducing the risk of errors and improving the overall quality of the final product.

  2. Increased efficiency: The new features in RS-274X, such as aperture macros and nested apertures, help to streamline the design process and reduce the time required to create complex PCB layouts.

  3. Better communication: The inclusion of attributes and other metadata in RS-274X files helps to improve communication between designers and manufacturers, reducing the risk of misinterpretation and errors.

  4. Reduced file size: Aperture macros and other features in RS-274X help to reduce the overall file size of Gerber files, making them easier to store, transfer, and process.

  5. Compatibility: RS-274X is widely supported by EDA software tools and PCB manufacturers, ensuring compatibility and ease of use throughout the design and manufacturing process.

Frequently Asked Questions (FAQ)

  1. Q: Is RS-274X compatible with older versions of Gerber?
    A: Yes, RS-274X is backward compatible with older versions of Gerber, such as RS-274D. However, older software and hardware may not support the new features introduced in RS-274X.

  2. Q: What software tools support RS-274X?
    A: Most modern EDA software tools, such as Altium Designer, KiCad, and Eagle, support RS-274X. It is essential to check the specific software documentation for compatibility information.

  3. Q: How do I convert my existing Gerber files to RS-274X?
    A: Many EDA software tools offer the option to export Gerber files in the RS-274X format. Consult your software’s documentation for specific instructions on how to export or convert files to RS-274X.

  4. Q: Can RS-274X handle multi-layer PCB designs?
    A: Yes, RS-274X is capable of handling multi-layer PCB designs. Each layer of the design is typically represented by a separate Gerber file, and these files can be combined to create the complete PCB layout.

  5. Q: Are there any limitations to using RS-274X?
    A: While RS-274X is a significant improvement over the original Gerber format, it still has some limitations. For example, it does not support 3D modeling or advanced design rule checks (DRCs). However, for most PCB design and manufacturing purposes, RS-274X is more than sufficient.


RS-274X, or Extended Gerber, is a powerful and versatile file format that has revolutionized the PCB design and manufacturing industry. By introducing new features and capabilities, such as aperture macros, polarity control, and attributes, RS-274X has made it easier for designers to create complex, high-quality PCB layouts. The format’s compatibility with modern EDA software tools and its wide acceptance by PCB manufacturers have made it an essential standard in the industry.

As PCB designs continue to become more complex and demanding, the importance of using a robust and flexible file format like RS-274X will only continue to grow. By understanding the features and advantages of this format, PCB designers and manufacturers can ensure that they are creating the best possible products while streamlining their workflows and reducing the risk of errors.

In summary, RS-274X is a critical tool in the world of PCB design and manufacturing, and its continued development and adoption will play a significant role in shaping the future of the electronics industry.

Feature Description
Aperture Macros Define complex shapes and patterns for reuse
Polarity Control Specify whether an area should be filled or unfilled
Interpolation Support for linear, circular, and arc interpolation
Nested Apertures Allow one aperture to contain another aperture
Attributes Assign information to apertures, draws, and other elements

Table 1: Key features of RS-274X (Extended Gerber)

Advantage Description
Improved accuracy More precise and detailed PCB layouts
Increased efficiency Streamlined design process and reduced time
Better communication Improved communication between designers and manufacturers
Reduced file size Easier to store, transfer, and process files
Compatibility Widely supported by EDA software tools and PCB manufacturers

Table 2: Advantages of using RS-274X (Extended Gerber)