How to Generate Gerber X2 Files in Altium Designer: A Complete Guide

If you’ve been designing PCBs for any length of time, you know that getting manufacturing files right is just as critical as the design itself. As someone who has dealt with countless manufacturing handoffs, I can tell you that switching to Gerber X2 files in Altium Designer has significantly reduced the back-and-forth with fab houses and eliminated many common miscommunication issues. This guide walks you through everything you need to know about generating Gerber X2 files in Altium Designer.

What is Gerber X2 Format and Why Does It Matter?

Gerber X2 is an enhanced version of the traditional Gerber RS-274X format that adds intelligent metadata to your manufacturing files. Released by Ucamco in February 2014, Gerber X2 transforms what was essentially a “dumb” image format into a smart data transfer format that your manufacturer’s CAM software can actually understand.

The traditional RS-274X format works fine for describing copper patterns, but it lacks context. When you send RS-274X files, your manufacturer has to manually interpret which file is the top copper layer, which is the solder mask, and how everything stacks together. Gerber X2 eliminates this guesswork by embedding attributes directly into each file.

Key Advantages of Gerber X2 Over RS-274X

Feature	RS-274X (Traditional)	Gerber X2
Layer Function	Manual interpretation required	Embedded in file attributes
Stack-up Information	Separate documentation needed	Included automatically
Pad Function	Not specified	Clearly defined (via, component, etc.)
Impedance Data	Separate notes required	Can be embedded
Part Type	Manual identification	Autodetected (single, panel, coupon)
Backward Compatibility	N/A	Fully compatible with RS-274X viewers

The beauty of Gerber X2 is its backward compatibility. If your manufacturer hasn’t upgraded their CAM software, they can still process your X2 files as standard RS-274X files, they just won’t benefit from the additional metadata.

Understanding Gerber X2 Attributes in Altium Designer

Before diving into the export process, let’s understand what attributes Altium Designer embeds in your Gerber X2 files. These attributes are what make X2 “intelligent” compared to traditional Gerber formats.

File Attributes

These describe the entire file and are placed at the beginning of each Gerber file:

Attribute	Description	Example Values
.FileFunction	Identifies the layer type	Copper,L1,Top / SolderMask,Top / Legend,Top
.FilePolarity	Whether layer is additive or subtractive	Positive / Negative
.Part	Type of design represented	Single / CustomerPanel / ProductionPanel / Coupon
.GenerationSoftware	Software that created the file	Altium,Altium Designer,XX.X

Aperture Attributes

These describe individual features within the file:

Attribute	Description	Purpose
.AperFunction	Function of the aperture	Identifies if pad is via, component, SMD, etc.
.DrillTolerance	Drilling tolerance	Specifies acceptable variation
.FlashText	Text strings	Preserves text information

Step-by-Step Guide to Generate Gerber X2 Files in Altium Designer

Now let’s get into the practical steps. Altium Designer provides two methods for generating Gerber X2 files: directly from the PCB editor or through an Output Job file. I’ll cover both approaches.

Method 1: Direct Export from PCB Editor

This is the quickest method for one-off exports or when you’re iterating on a design.

Step 1: Open the Gerber X2 Setup Dialog

With your PCB document open and active, navigate to File → Fabrication Outputs → Gerber X2 Files. This opens the Gerber X2 Setup dialog.

Step 2: Configure General Settings

On the left side of the dialog, configure these essential parameters:

Setting	Recommended Value	Notes
Units	Millimeters	Most manufacturers prefer metric; confirm with your fab
Format	4:5	Provides 0.00001 mm precision; sufficient for most designs
File Subject	Autodetect	Let Altium determine if it’s single board, panel, or coupon
File Comment	Optional	Add project name or revision if helpful

Step 3: Select Layers to Plot

Click on the Layers to Plot tab. Here you’ll see all available layers in your design. For a typical 2-layer board, select:

• Top Layer (signal)
• Bottom Layer (signal)
• Top Overlay (silkscreen)
• Bottom Overlay (silkscreen)
• Top Solder (solder mask)
• Bottom Solder (solder mask)
• Top Paste (paste mask)
• Bottom Paste (paste mask)
• Keep-Out Layer (board outline)
• Mechanical Layer (if used for outline or dimensions)

For multilayer boards, include all internal copper layers and any additional mechanical layers your design uses.

Pro tip: Use Plot Layers → Used On to quickly select all layers that contain actual data in your design.

Step 4: Configure Drill Drawings

Click the Drills Drawing tab to configure drill output. Select the appropriate layer pairs:

• Top Layer – Bottom Layer: For through-hole drilling
• Any blind/buried via pairs: If your design uses HDI features
• Backdrill pairs: If backdrilling is required

Step 5: Generate Files

Click OK to generate the Gerber X2 files. The output will be saved to the location specified in your project options (Project → Project Options → Options tab → Output Path field).

Method 2: Using Output Job Files (Recommended for Production)

For production-ready designs, I strongly recommend using Output Job files. They provide consistency across projects and make it easy to regenerate outputs without reconfiguring settings.

Step 1: Create a New Output Job

Right-click on your project in the Projects panel and select Add New to Project → Output Job File. This creates a new .OutJob file.

Step 2: Add Gerber X2 Output

In the Output Job editor, right-click under Fabrication Outputs and select Add New Fabrication Output → Gerber X2 Files. Then select your PCB document as the data source.

Step 3: Configure the Output

Right-click on the newly created Gerber X2 entry and select Configure. This opens the same Gerber X2 Setup dialog described above. Configure your settings and click OK.

Step 4: Set Up Output Container

In the Output Containers section, configure where files will be saved. You can choose:

• Folder structure (recommended for organization)
• PDF output (for documentation)
• Release container (for version-controlled releases)

Step 5: Generate Content

Select the outputs you want to generate and click Generate Content in the right-hand panel. All selected outputs will be generated according to your configuration.

Recommended Gerber X2 Export Settings for Common Scenarios

Different manufacturing requirements call for different settings. Here are optimized configurations for common scenarios:

Standard 2-Layer PCB for Prototyping

Setting	Value
Units	Millimeters
Format	4:5
File Subject	Single
Layers	Top, Bottom, Top/Bottom Overlay, Top/Bottom Solder, Keep-Out
Drill Drawing	Top Layer – Bottom Layer only

4+ Layer Production Board

Setting	Value
Units	Millimeters
Format	4:5
File Subject	Autodetect
Layers	All signal layers, all plane layers, both overlays, both solder masks, both paste masks, mechanical outline
Drill Drawing	All used layer pairs

Panel/Array for Volume Production

Setting	Value
Units	Millimeters
Format	4:5
File Subject	CustomerPanel or ProductionPanel
Layers	All layers as configured in panel design
Include	Panel outline, tooling holes, fiducials

Additional Manufacturing Files to Generate

Gerber X2 files alone aren’t sufficient for manufacturing. You’ll also need these complementary files:

NC Drill Files

Navigate to File → Fabrication Outputs → NC Drill Files to generate drill data. Use these settings:

Setting	Recommended Value
Units	Same as Gerber files (Millimeters)
Format	Same as Gerber files (4:5)
Generate separate files	Enable for plated/non-plated holes

Pick and Place Files

For assembly, generate pick and place data via File → Assembly Outputs → Generates pick and place files. This provides component positions and rotations for automated assembly.

Bill of Materials (BOM)

Generate a BOM through Reports → Bill of Materials or include it in your Output Job file for a complete manufacturing package.

Verifying Your Gerber X2 Files Before Submission

Never submit manufacturing files without verification. Here are the tools and steps I use to validate Gerber X2 exports:

Built-in CAMtastic Viewer

Altium Designer automatically opens generated Gerber files in its CAMtastic viewer. Use this to:

• Verify all layers are present
• Check that layer alignment is correct
• Confirm board outline is properly defined
• Inspect critical features like fine-pitch pads

Free External Gerber X2 Viewers

Tool	Features	Best For
HQDFM (NextPCB)	Online, DFM analysis, layer auto-alignment	Quick verification + DFM checks
Altium 365 Viewer	Online, supports X2, compare revisions	Sharing with team/manufacturer
ZofzPCB	3D visualization, layer stack view	Visual stack-up verification
KiCad GerbView	Free, reads X2 job files, measurements	Detailed inspection
Gerbv	Free, open source, multi-platform	Basic viewing
Reference Gerber Viewer	Official Ucamco viewer	Format compliance verification

Verification Checklist

Before sending files to your manufacturer, verify:

• All copper layers are present and correctly ordered
• Solder mask layers show proper pad openings
• Silkscreen doesn’t overlap pads
• Board outline is a closed contour
• Drill files match the copper layer hole locations
• No unintended features on any layer
• File naming clearly identifies each layer

Troubleshooting Common Gerber X2 Export Issues

Even experienced designers encounter problems occasionally. Here are solutions to common issues:

Missing Layers in Export

Problem: Some layers don’t appear in the exported files.

Solution: Check that the layers are enabled in the Layer to Plot tab. Also verify that the layers actually contain data, empty layers won’t generate output files.

Incorrect Layer Order

Problem: Manufacturer reports layer stack doesn’t match intent.

Solution: Verify your layer stack in Altium’s Layer Stack Manager matches your design intent. Gerber X2 embeds this information automatically, but it must be correct in your design first.

Aperture Errors

Problem: CAM software reports invalid or missing apertures.

Solution: Ensure all pads and vias have proper flash shapes defined. Check for zero-width traces or non-standard primitives that might not export correctly.

File Size Too Large

Problem: Generated files are unusually large.

Solution: Check for excessive polygon vertices or unnecessary precision. Consider simplifying copper pours or reducing the coordinate format precision if appropriate.

Gerber X2 vs Other Manufacturing Formats

While this guide focuses on Gerber X2, it’s worth understanding how it compares to alternatives:

Format	Intelligence Level	Adoption	Best For
Gerber RS-274X	Low (image only)	Universal	Legacy systems
Gerber X2	Medium (image + attributes)	Growing	General production
Gerber X3	High (includes assembly data)	Emerging	Advanced workflows
ODB++	High (proprietary)	High	Volume production
IPC-2581	High (open standard)	Growing	Industry 4.0 integration

For most projects, Gerber X2 offers the best balance of intelligence and compatibility. If your manufacturer supports ODB++ or IPC-2581, consider those formats for even richer data transfer.

Resources for Altium Designer Users

Here are valuable resources for mastering Gerber X2 exports and PCB manufacturing:

Official Documentation

• Altium Designer Documentation: altium.com/documentation – Complete technical documentation
• Ucamco Gerber Format Specification: ucamco.com – Official Gerber X2 specification
• Reference Gerber Viewer: Available from Ucamco for format compliance testing

Free Tools

• Altium 365 Viewer: altium.com/viewer – Free online Gerber viewer
• HQDFM Online Viewer: nextpcb.com/free-online-gerber-viewer – DFM analysis included
• ZofzPCB: zofzpcb.com – 3D Gerber visualization
• KiCad GerbView: kicad.org – Free, supports X2 metadata

Manufacturer Resources

• JLCPCB Gerber Guide: Specific requirements for JLCPCB orders
• PCBWay Help Center: Detailed Altium export tutorials
• Sierra Circuits Knowledge Base: Advanced manufacturing insights

Frequently Asked Questions

Should I use Gerber X2 or stick with RS-274X?

Use Gerber X2 whenever possible. It’s backward compatible, so even if your manufacturer’s CAM software doesn’t fully support X2, they can still process the files. The embedded metadata reduces errors and speeds up CAM processing for manufacturers who do support it.

Do all PCB manufacturers accept Gerber X2 files?

Most modern manufacturers accept Gerber X2 files. Since X2 is backward compatible with RS-274X, any manufacturer that accepts standard Gerber files can process X2 files. However, to benefit from the enhanced metadata, the manufacturer needs X2-capable CAM software. When in doubt, ask your manufacturer.

What’s the difference between Gerber X2 and Gerber X3?

Gerber X3, released in 2020, extends X2 by incorporating component and assembly data directly into the Gerber files. While X2 focuses on fabrication data, X3 adds information traditionally found in pick-and-place files. X3 adoption is still emerging, but it represents the future direction of the Gerber format.

Can I generate both RS-274X and Gerber X2 from the same Altium project?

Yes, absolutely. You can create multiple output configurations in an Output Job file, one for RS-274X and another for Gerber X2. This is useful when working with multiple manufacturers who have different capabilities.

How do I know if my Gerber X2 files were generated correctly?

Use a Gerber viewer that supports X2 attributes to verify your files. The Altium 365 Viewer, HQDFM, or KiCad’s GerbView can read X2 metadata and confirm that layer functions and attributes are correctly embedded. Also check that your layer count matches expectations and that all features are visible on each layer.

Conclusion

Generating Gerber X2 files in Altium Designer is straightforward once you understand the process and settings involved. The key advantages of using X2 over traditional RS-274X, embedded layer information, automatic attribute assignment, and reduced manual interpretation, make it well worth adopting for your manufacturing workflow.

Whether you’re prototyping a simple 2-layer board or preparing complex multilayer designs for volume production, Gerber X2 provides a more reliable data transfer method that reduces errors and improves communication with your manufacturer. The format’s backward compatibility means you can start using it today without worrying about manufacturer support, any fab house that accepts standard Gerber files can process your X2 outputs.

Take the time to set up proper Output Job configurations for your common project types. The initial investment in creating standardized export settings pays dividends in consistency and reduced setup time for future projects. And always, always verify your manufacturing files before submission, a few minutes with a Gerber viewer can save days of manufacturing delays.

The PCB industry continues to evolve toward more intelligent data formats, and Gerber X2 represents an important step in that direction. By mastering X2 exports in Altium Designer, you’re positioning yourself for smoother manufacturing handoffs today while preparing for even more advanced formats in the future.