How to Convert DWG to Gerber Files: The Complete Guide for AutoCAD Users

Working with AutoCAD for PCB design and then hitting a wall when your manufacturer asks for Gerber files? You’re in good company. About 10-15% of all PCB and RF layouts are still created in mechanical CAD tools like AutoCAD, and nearly every one of those designers eventually faces the same conversion challenge.

I’ve spent years helping engineers navigate this exact problem, and I can tell you that most conversion headaches stem from a fundamental mismatch between what AutoCAD can do and what Gerber files actually need. This guide covers everything you need to know about converting DWG files to Gerber format, from choosing the right tools to avoiding the mistakes that send boards back for rework.

Understanding the DWG File Format

Before we tackle conversion, let’s establish what we’re working with. Understanding DWG’s structure explains why conversion isn’t as straightforward as a simple “Save As” operation.

What is a DWG File?

DWG (short for “drawing”) is Autodesk’s native file format for AutoCAD, first introduced in the early 1980s. Unlike DXF (Drawing Exchange Format), which uses human-readable ASCII text, DWG stores data in binary format. This makes DWG files approximately 25% smaller than their DXF equivalents while maintaining complete fidelity to the original design.

The format supports an extensive range of entity types that make AutoCAD so powerful for mechanical and architectural work. You can create complex geometries including 3D objects, hatches, splines, regions, and sophisticated text formatting. This flexibility is exactly why many RF and microwave engineers choose AutoCAD over traditional EDA tools when they need geometric precision that dedicated PCB software can’t provide.

Why Engineers Design PCBs in AutoCAD

AutoCAD remains popular for electronic design in specific scenarios. RF and microwave circuits often require custom geometries that standard EDA tools struggle to handle. MEMS designs need precise mechanical features integrated with electrical components. Chemical milling artwork demands the geometric accuracy that AutoCAD delivers. Some companies have decades of legacy designs in DWG format that need occasional updates.

The problem arises when these designs need to go to manufacturing. PCB fabricators work with Gerber files, not DWG or DXF. And unlike architectural drawings that might print directly from AutoCAD, circuit boards require photoplotter-ready data that Gerber format provides.

What is a Gerber File and Why Manufacturers Require It

Gerber has been the industry standard for PCB manufacturing for over 35 years. Understanding why manufacturers insist on this format helps explain the conversion challenges.

The Gerber Format Explained

Gerber files are remarkably simple compared to DWG. Each file is essentially an ASCII text document containing X,Y coordinates paired with aperture definitions (shapes). There’s no ambiguity about interpretation. What the file describes is exactly what the photoplotter will image.

Each Gerber file represents a single PCB layer. A typical two-layer board might require six or more Gerber files: top copper, bottom copper, top solder mask, bottom solder mask, top silkscreen, and board outline. More complex boards add internal copper layers, additional silk layers, and paste masks.

Key Differences Between DWG and Gerber Files

Characteristic	DWG Format	Gerber Format
Data Structure	Binary with hundreds of entity types	ASCII text with X,Y coordinates and apertures
Dimensionality	2D and 3D support	Strictly 2D
Layer Handling	Flexible, user-defined layers	Strict PCB layer types (copper, mask, silk)
Text Support	TrueType fonts, complex formatting	Simple stroke fonts only
Fill Patterns	Complex hatches, gradients	Simple solid fills
File Size	Compact binary encoding	Larger but universal
Primary Use	Design and documentation	Manufacturing output

Why PCB Manufacturers Won’t Accept DWG Files

Most fabricators refuse to work directly with DWG files for several reasons. The format requires interpretation since the same visual result can be achieved using different entity types. A filled area might be a hatch, a region, or a closed polyline. Each requires different handling, and any misinterpretation leads to manufacturing errors.

Additionally, DWG files often contain non-manufacturing elements like dimension annotations, construction lines, and title blocks. Someone needs to identify and filter these out, adding time and introducing potential errors.

Gerber eliminates these problems. The format contains only manufacturing-relevant data with no interpretation required. What you see in a Gerber viewer is exactly what will be manufactured.

DWG to Gerber Conversion Methods

There are three primary approaches to converting DWG files to Gerber format, each with distinct advantages and limitations.

Method 1: Direct Conversion Using AutoCAD Plugins

The most streamlined approach uses plugins that add Gerber export capability directly within AutoCAD. This method keeps your entire workflow inside a single application.

EasyGerb by Numerical Innovations

EasyGerb is the most widely recommended AutoCAD plugin for Gerber export. It runs as an ARX application directly inside AutoCAD (versions 2013 through 2025 are supported), allowing you to select entities and generate Gerber files without leaving your familiar environment.

Key features include:

• Direct export to RS-274X (Extended Gerber) format
• Selective entity conversion using AutoCAD’s selection tools
• NC drill file generation for through-holes
• Support for multiple layer mapping configurations

Loading EasyGerb in AutoCAD:

1. Type APPLOAD at the command prompt
2. Navigate to the EasyGerb installation folder
3. Select the version matching your AutoCAD installation
4. Click “Load” to activate the plugin
5. Type EasyGerb at the command prompt to launch the interface

Once loaded, EasyGerb automatically loads with subsequent AutoCAD sessions.

Method 2: Standalone Conversion Software

If you prefer to keep your AutoCAD installation unchanged, standalone converters can process DWG files directly or work with exported DXF files.

Recommended Standalone DWG to Gerber Converters

Software	Key Features	Best For	Pricing
FAB 3000	Full CAM editor, DFM checks, DWG/DXF import	Professional production work	Commercial
ACE 3000	Specialized 2D/3D translator, batch processing	High-volume conversions	Commercial
GerbView	View and convert multiple formats, comparison tools	Viewing and verification	Commercial
reaConverter	Batch conversion, command-line support	Automated workflows	Commercial

FAB 3000 Workflow:

FAB 3000 provides the most comprehensive conversion and verification workflow:

1. Launch FAB 3000 and create a new project
2. Import your DWG file using File → Import → DWG
3. Configure import settings (units, layer mapping)
4. Review the imported design and verify accuracy
5. Assign layers to appropriate Gerber types
6. Run DFM checks to catch potential manufacturing issues
7. Export to Gerber RS-274X format

Method 3: DWG to DXF to Gerber Two-Step Conversion

Some workflows benefit from converting DWG to DXF first, then processing the DXF file. This approach provides an intermediate step where you can verify the data before final Gerber generation.

Why Use Two-Step Conversion:

• DXF files are human-readable, making troubleshooting easier
• Some converters handle DXF more reliably than DWG
• Provides a checkpoint to catch problems early
• Works with converters that only support DXF input

Exporting DXF from AutoCAD:

1. Open your DWG file in AutoCAD
2. Run AUDIT and PURGE to clean the drawing
3. Select File → Save As
4. Choose DXF format from the file type dropdown
5. Select the appropriate DXF version (AutoCAD 2010 DXF works broadly)
6. Save the file

The resulting DXF can then be processed by any DXF-to-Gerber converter.

Preparing Your DWG File for Successful Conversion

The quality of your conversion depends heavily on how your DWG file is structured. Following these preparation steps dramatically improves conversion success rates.

The Five Fundamental Entities for Gerber Conversion

Gerber files can only represent a limited set of geometric elements. For reliable conversion, build your DWG designs using these five entity types:

1. Polylines (LW Polylines)

Polylines are the workhorses of DWG to Gerber conversion, representing roughly 80% of typical PCB layouts. Use polylines with width for traces and tracks. Use closed, zero-width polylines to define filled area boundaries.

2. Circles

Circles translate directly to circular apertures in Gerber. Use them for round pads, via definitions, and circular features.

3. Text (SHX Fonts)

Stick fonts (AutoCAD’s SHX format) convert cleanly because they’re defined as stroke segments rather than filled shapes. Avoid TrueType fonts, which create complex filled geometries that may not convert correctly.

4. Blocks

Blocks let you create reusable components like standard pad shapes or via structures. They convert successfully when their internal entities follow the fundamental entity rules.

5. Inserts

Inserts are instances of blocks placed in your drawing. Use them for repetitive elements to keep your design organized and efficient.

DWG Entities That Cause Conversion Problems

Entity Type	Problem	Solution
Hatches	Complex fill algorithms don’t translate to Gerber	Redraw as closed polylines
Splines	Gerber only supports lines and arcs	Convert to polylines with arc approximation
3D Objects	Gerber is strictly 2D	Flatten to 2D or remove
TrueType Text	Creates filled shapes that may convert incorrectly	Switch to SHX fonts
Regions	Require complex boolean operations	Explode to polylines
Dimensions	Not manufacturing data	Move to non-exported layer or delete
Xrefs	External references may not import	Bind xrefs before conversion

Pre-Conversion Checklist for DWG Files

Before attempting conversion, verify these items in your DWG file:

Geometry Verification:

• All manufacturing geometry uses supported entity types
• No self-intersecting boundaries in filled areas
• Polyline widths match intended trace widths
• Circles are on appropriate layers for pads or drills

Layer Organization:

• Each PCB layer on a separate AutoCAD layer
• Clear, consistent layer naming
• Non-manufacturing content (dimensions, notes) on excluded layers

Settings Verification:

• Drawing units match your design intent (metric vs. imperial)
• Design is positioned near the origin
• LTSCALE is set appropriately for line types
• AUDIT shows no errors

Step-by-Step DWG to Gerber Conversion Process

Here’s the complete workflow I use for reliable conversions:

Step 1: Clean Your DWG File

Open the file in AutoCAD and run these commands:

AUDIT (fix any errors)PURGE (remove unused elements)OVERKILL (remove duplicate geometry)

Review and delete any construction geometry, reference dimensions, or annotations that shouldn’t appear in manufacturing files.

Step 2: Organize Layers for Export

Create a clear layer structure that maps to Gerber output:

AutoCAD Layer	Gerber Output	Description
TOP_COPPER	.GTL	Top copper layer
BOT_COPPER	.GBL	Bottom copper layer
TOP_SOLDERMASK	.GTS	Top solder mask
BOT_SOLDERMASK	.GBS	Bottom solder mask
TOP_SILK	.GTO	Top silkscreen
BOT_SILK	.GBO	Bottom silkscreen
BOARD_OUTLINE	.GKO	Board mechanical outline
DRILLS	.DRL	NC drill file (Excellon format)

Step 3: Convert to Gerber Format

Using your chosen conversion tool (EasyGerb, FAB 3000, or similar):

1. Import or select the DWG data
2. Configure units to match your design
3. Map AutoCAD layers to Gerber layer types
4. Set output format to RS-274X (Extended Gerber)
5. Configure coordinate precision (2:5 or 2:6 for inches)
6. Generate output files

Step 4: Generate Drill Files

Drill data requires separate handling in Excellon format:

1. Ensure all drill hits are circles on a designated layer
2. Export drill data with tool sizes defined
3. Verify drill file coordinates match Gerber registration

Step 5: Validate Output Files

Never send Gerbers to manufacturing without verification:

1. Load all Gerber files in a viewer (GerbView, ViewMate, KiCad GerbView)
2. Check layer alignment by overlaying multiple layers
3. Verify dimensions match original design
4. Confirm all features are present and correctly sized
5. Review drill file for correct hole sizes and positions

Troubleshooting Common DWG to Gerber Conversion Issues

Problem: Output Looks Nothing Like Original Design

Cause: Unsupported entity types filtered out during conversion

Solution: Identify which entities didn’t convert by comparing layer-by-layer. Redraw those elements using supported entity types (polylines, circles, SHX text).

Problem: Filled Areas Appear as Outlines

Cause: Hatches or improper boundary definitions

Solution: Replace hatches with closed polylines. Ensure boundary polylines have zero width and are continuous with no gaps.

Problem: Scale or Position is Wrong

Cause: Unit mismatch or incorrect origin setting

Solution: Verify units in both AutoCAD and converter settings. Position design near origin before export. Use reference dimensions to confirm scale.

Problem: Text is Missing or Garbled

Cause: TrueType fonts not supported by converter

Solution: Change all text to SHX (stick) fonts. Alternatively, explode text to polylines before conversion, though this loses editability.

Problem: Drill Holes Not Appearing

Cause: Circles not on designated drill layer, or drill export overlooked

Solution: Move all drill circles to a dedicated layer. Generate Excellon drill file separately from Gerber exports.

Useful Resources and Software Downloads

Conversion Software

Resource	URL	Notes
EasyGerb	numericalinnovations.com/collections/easygerb	AutoCAD plugin, demo available
FAB 3000	numericalinnovations.com	Full CAM software, 30-day trial
ACE 3000	numericalinnovations.com	2D/3D translator
GerbView	gerbview.com	Viewer and converter, 30-day trial
reaConverter	reaconverter.com	Batch conversion tool

Free Gerber Viewers for Validation

Viewer	Platform	Features
KiCad GerbView	Windows, Mac, Linux	Full-featured, open source
ViewMate Free	Windows	Basic viewing and measurement
ZofzPCB	Windows	3D visualization
PCB Preflight	Web	Online viewer with collaboration

Documentation and Guides

• Gerber Format Specification: ucamco.com/en/gerber
• Bay Area Circuits Conversion Guide: bayareacircuits.com/dxf-to-gerber-conversion-guide/
• Numerical Innovations DXF/DWG Guidelines: numericalinnovations.com/dxf-conversions

Best Practices for DWG to Gerber Conversion

After handling hundreds of conversions, these practices consistently produce the best results:

1. Design with Conversion in Mind

If you know your DWG will eventually become Gerber files, use only the five fundamental entity types from the start. Retrofitting a complex design is far more work than building it correctly initially.

2. Keep Layers Strictly Organized

One AutoCAD layer should map to exactly one Gerber file. Mixing copper and silk on the same layer creates sorting headaches during conversion.

3. Work Near the Origin

Designs positioned far from the origin (X=2000mm, for example) often cause coordinate overflow or precision issues. Keep your geometry close to 0,0.

4. Maintain Unit Consistency

Decide on metric or imperial at the start and stick with it throughout design and conversion. Mixed units cause scaling errors that may not be obvious until boards come back wrong.

5. Document Your Layer Mapping

Keep a record of which AutoCAD layers map to which Gerber files. This makes revisions easier and reduces errors when you return to a project months later.

6. Always Verify Before Manufacturing

Load your Gerbers in a viewer, check dimensions, overlay layers to verify alignment. The few minutes spent checking can save weeks of manufacturing delays.

Frequently Asked Questions About DWG to Gerber Conversion

Can I Convert DWG to Gerber Directly in AutoCAD Without Plugins?

No, AutoCAD does not include native Gerber export capability. You must use either a third-party plugin like EasyGerb that runs inside AutoCAD, or standalone conversion software that imports DWG files. Some users export to DXF first and then convert the DXF to Gerber, but this still requires external software.

What is the Best Free DWG to Gerber Converter?

Truly free options for DWG to Gerber conversion are limited. Your best approach is to export DXF from AutoCAD (free within AutoCAD), then use a free or trial version of conversion software. KiCad can import DXF files and export Gerbers, though it requires manual layer setup. Most dedicated converters like FAB 3000 and EasyGerb offer trial periods that may be sufficient for occasional use.

Should I Convert DWG to DXF First Before Creating Gerber Files?

Converting to DXF first can be helpful for troubleshooting since DXF is human-readable text. However, direct DWG conversion typically produces better results because DWG is more compact and experiences fewer parsing errors. If your converter supports DWG import directly, use that. Reserve the two-step approach for situations where direct conversion fails.

Why Does My Manufacturer Refuse to Accept DWG Files?

PCB manufacturers require Gerber files because they provide unambiguous manufacturing instructions. DWG files require interpretation since they can contain hundreds of different entity types, non-manufacturing elements (dimensions, notes), and complex features that don’t translate to PCB fabrication. Gerber eliminates interpretation errors and provides data that photoplotters can process directly.

How Do I Handle Drill Holes When Converting DWG to Gerber?

Drill data must be exported separately in Excellon format, not as part of the Gerber files. In your DWG file, place all drill holes as circles on a dedicated layer. During conversion, generate the Excellon drill file from this layer while generating Gerber files from your other layers. Verify that drill coordinates align with your Gerber data using a viewer that displays both formats.

Conclusion

Converting DWG files to Gerber format is entirely achievable once you understand the fundamental differences between these formats. The key is preparation: structure your DWG files using the five fundamental entity types, organize your layers cleanly, and verify your output before sending to manufacturing.

Whether you choose a direct AutoCAD plugin like EasyGerb or standalone software like FAB 3000, the conversion process follows the same basic principles. Import your data, map layers to Gerber types, configure output settings, and validate the results.

Most conversion problems trace back to using unsupported entity types in the original DWG. If you’re starting a new design that will eventually need Gerber output, build it with conversion in mind from day one. If you’re working with legacy files, invest the time to simplify problematic entities before attempting conversion.

The extra effort spent on proper preparation pays dividends in faster manufacturing turnaround and fewer costly errors. A well-converted Gerber file set sails through fabrication without holds or questions, getting your boards built correctly the first time.