How to Fix the “PCB File Too Large” Error When Exporting Gerber Files in Altium Designer
When using Altium Designer to export Gerber files, you may occasionally receive an error indicating that the PCB file is too large to be exported.
This problem is usually not caused by the actual size of the circuit board. In most cases, the PCB document contains unwanted graphical objects, residual design data, or components located far outside the actual board area.
When these objects are included in the output data, Altium Designer may interpret them as valid PCB information. As a result, the overall document area becomes excessively large and may exceed the allowable output range for Gerber generation.
For engineers preparing files for PCB manufacturing, identifying and removing these unnecessary objects before production is an important step.
Why Does Altium Designer Report That the PCB File Is Too Large?
There are two common causes of this problem.
1. Old PCB Data Was Not Completely Removed
A common situation occurs when a designer reuses an existing PCB document for a new project.
Instead of creating a completely new file, the previous board is modified and reused. Some old tracks, components, mechanical drawings, dimensions, text, or other graphical objects may remain hidden or overlooked.
Although these objects may not be part of the actual circuit, they can still affect the document’s overall coordinate range.
During Gerber generation, the software may therefore attempt to process these unwanted objects.
2. Components or Graphics Are Located Far Outside the Board
Another common cause is that a component or graphic object has accidentally been placed far away from the actual PCB.
For example, a component may appear hundreds of millimeters away from the board because it was accidentally moved during layout.
When you use the document-fit function, the actual PCB may appear very small and located in only one corner of the workspace. This is a strong indication that there is unwanted data outside the board area.
Before sending production files to a PCB fabrication supplier, these objects should be identified and removed.
How to Check for Unwanted PCB Data
The first step is to determine whether the document contains objects outside the actual board.
In Altium Designer, press Ctrl + PgDn or use View → Fit Document.
This command adjusts the view so that all objects contained in the document are displayed.
If the PCB occupies only a small portion of the screen while the rest of the workspace is empty, check the document carefully for:
- Components located outside the board
- Unused footprints
- Old copper tracks
- Mechanical drawings
- Dimensions
- Text or labels
- Imported DXF or CAD graphics
- Previous PCB design data
- Other unintended graphical objects
Cleaning these objects is especially important before submitting files for PCB manufacturing.
For projects requiring professional layout review, you can also refer to the PCB Design & Layout Service available through GOPCBA for additional design and manufacturability support.
Step-by-Step Solution for the “PCB File Too Large” Error
Step 1: Set the PCB Origin
First, set a suitable origin point near the lower-left corner of the actual PCB.
In Altium Designer, select:
Edit → Origin → Set
Then click an appropriate point near the lower-left corner of the board.
Setting a clean origin helps establish a reasonable coordinate reference for the PCB and makes it easier to identify objects that are positioned far outside the intended design area.
Step 2: Select All Objects
Press:
Ctrl + A
Alternatively, select:
Edit → Select All
This selects all objects currently contained in the PCB document.
At this stage, do not immediately delete anything. Carefully inspect the selected objects to ensure that the actual PCB design and all required production information are included.
Step 3: Deselect the Actual PCB Area
Use the following command:
Edit → DeSelect → Inside Area
Then draw a large selection box around the actual PCB.
The purpose of this operation is to remove the selection from the legitimate PCB area while keeping unwanted objects outside the board selected.
This step requires particular attention because an incorrectly positioned selection box could cause legitimate design information to be selected.
Step 4: Delete the Unwanted Objects
Once you have confirmed that only unwanted objects outside the PCB remain selected, press:
Ctrl + X
or select:
Edit → Cut
This removes the unwanted graphical data from the document.
The objective is to leave only the actual PCB design and the necessary manufacturing information.
For complex boards, it is recommended to perform a detailed PCB design review before continuing with manufacturing documentation.
Step 5: Carefully Verify the PCB Design
This is one of the most important steps in the entire process.
Before generating production files, carefully inspect the PCB to make sure that no legitimate objects have been accidentally removed.
Check the following items:
- Board outline
- Copper traces
- Pads
- Vias
- Component footprints
- Solder mask information
- Silkscreen
- Mechanical layers
- Drill information
- Dimensions
- Required manufacturing notes
For more complex designs, reviewing the complete production data before fabrication can help prevent manufacturing delays and incorrect boards.
Step 6: Export the Gerber and Drill Files
After confirming that the PCB document contains only the required design information, export the Gerber files and drill files again.
The generated production package should be checked before being submitted to the manufacturer.
A typical PCB production package may include:
- Gerber copper layers
- Solder mask layers
- Silkscreen layers
- Board outline
- Drill files
- Additional mechanical or fabrication information when required
You can compare the exported data with the original board design to confirm that the complete PCB is represented correctly.
For additional information about production capabilities and supported board structures, see the PCB Manufacturing service page.
How to Prevent the Problem in Future PCB Projects
The “PCB file too large” error is usually preventable with a few basic design practices.
Keep the PCB Workspace Clean
Avoid leaving unused components, footprints, drawings, dimensions, or imported graphics outside the board.
If you reuse an existing project, remove unnecessary data before starting the new design.
Check the Document Extent Before Gerber Export
Always use View → Fit Document before generating production files.
If the PCB suddenly appears very small or is located in one corner of the workspace, investigate the document for objects outside the board.
Review the Production Data
Before sending files to a manufacturer, verify that the Gerber and drill data correctly represent the actual PCB.
Professional PCB fabrication workflows normally require clean production data, accurate board outlines, and consistent manufacturing information.
Why Clean Gerber Files Matter for PCB Manufacturing
Gerber files are one of the most important data sources used during PCB production.
Unwanted objects can cause problems such as:
- Incorrect board dimensions
- Unexpected copper features
- Incorrect board outlines
- Manufacturing data interpretation errors
- Delays during engineering review
- Additional communication with the manufacturer
- Potential production errors
For this reason, designers should always perform a final data check before submitting Gerber files for production.
If the PCB will also proceed directly to assembly, a clean manufacturing data package can simplify the transition from PCB fabrication to assembly and testing.
Final Checklist Before Exporting Gerber Files
Before completing the export process, confirm the following:
- The actual PCB is located correctly within the document.
- No unwanted components or graphics remain outside the board.
- The PCB origin is set appropriately.
- The board outline is complete and correct.
- All copper, solder mask, and silkscreen layers are correct.
- Drill information has been verified.
- No unnecessary design data remains in the document.
- The exported Gerber files have been reviewed.
- The drill files correspond correctly with the PCB design.
- The final production package is ready for PCB manufacturing.
Following these steps can effectively resolve the “PCB file too large” error in Altium Designer and help ensure that your production files accurately represent the intended PCB design.
If you need professional support for PCB fabrication, assembly, testing, or production preparation, you can contact GOPCBA through the official website.
