Gerber Viewer — PCB Layers & Drill Alignment Check
Preview supported Gerber and Excellon ZIP layers locally, check declared units and drill-centre alignment, and download SVG, HTML and JSON evidence.
Gerber Package Check
Keep the original production package. This is a bounded geometric viewer, not DFM certification.
Supported scope: Local ZIP · up to 32 layers · no macros, step-repeat or routed slots
Gerber package and documented settings
Required fields are marked with an asterisk.
Layer geometry and alignment evidence
Review your output, then save it to your device.
Make the next step clear.
Your findings, assumptions and next steps will appear here after you run the check.
Gerber Package Check · https://gerber.kitforma.com/ · KitForma
Actual layered SVG preview with millimetre normalization
Explicit missing-format handling and partial-package reporting
Downloadable geometry and drill-centre evidence
Understand the evidence.
Focused guides explain the rules, the edge cases and the checks worth doing before you act.
Check a Gerber package before handing it off
Inspect the files, shared coordinate system and missing evidence before passing a PCB fabrication package to someone else.
Read the guide ↗Field guide / 02Read Gerber and Excellon units without guessing scale
Understand explicit units, fixed-point coordinates and the differences between suppressed and retained zeros.
Read the guide ↗Field guide / 03Interpret drill alignment evidence without mistaking it for DFM
Use nearest flash centres and outline bounds as limited geometric evidence, with explicit unavailable and partial cases.
Read the guide ↗Before you start
Which Gerber features are supported?
Explicit absolute FS/MO Gerber with C, R, O and P apertures, lines, arcs, regions and dark/clear polarity. X2 file attributes help identify layers. Aperture macros, step-repeat, aperture blocks and advanced image transforms are explicitly excluded.
Does it support Excellon drills and routed slots?
Ordinary absolute circular drill hits are supported with explicit units and unambiguous decimal or documented fixed-point coordinates. Routed slots, repeat drilling and incremental coordinates are unsupported.
Will it guess missing units or move layers into alignment?
No. Missing drill settings can be supplied explicitly from export documentation and are recorded. Existing declarations remain authoritative. Layers retain their source origins and orientation; bottom layers are not mirrored.
Does a matching drill centre mean the board is manufacturable?
No. It only means that a circular drill centre is near a source copper flash centre. Final copper containment, annular rings, plating, electrical connectivity and manufacturing rules are not checked.
What happens when part of a ZIP is unsupported?
Supported layers can still be inspected, with a prominent partial result and a rejected-file list. Ignored non-layer files are listed in the full report. No missing geometry is invented.
What are the privacy and size limits?
Files are processed locally. ZIP: 16 MiB compressed and 48 MiB expanded; up to 32 recognized layers, 2 MiB each, 100,000 parsed commands and an 8 MiB combined SVG. Alignment accepts up to 20,000 copper flashes and 20,000 circular drill hits. SVG/HTML/JSON are review outputs, not modified production files.
Sources & assumptions
Formats, algorithms and supported features are documented below. Check the stated scope and inspect your output before using it.
- Ucamco Gerber reference viewer ↗
The format owner’s reference viewer and documentation provide an independent way to inspect production artwork.
- Tracespace v4.2.8 Gerber rendering API ↗
Local rendering uses the MIT-licensed v4.2.8 engine behind additional format, size and SVG validation.
- Tracespace v4.2.8 parser API ↗
Parser documentation for explicit Gerber and Excellon units, coordinate format and warning handling.
Reviewed 2026-10-17. Read our methodology or report an issue.