Free Online Gerber Viewer - View Gerber RS-274X & Excellon Drill Files Online for Free

Secure Gerber viewer with no upload — free, private, browser-only. View Gerber RS-274X and Excellon drill files online. ZIP batch import, multi-layer overlay, drag & drop. All data processed locally, never leaves your machine.

Drop your Gerber files here to start viewing — no registration, no upload, completely free.

Key Features

• Multi-layer Gerber RS-274X rendering — independent opacity, visibility toggle, and color-coded layers
• ZIP batch import with automatic decompression, macOS metadata filtering, and multi-file drag & drop
• Smart layer identification from filenames — auto-detects copper, solder mask, silkscreen, solder paste, drill, and board outline
• Precision measurement tools — single and continuous modes, real-time live preview during drag, distance, angle, dx/dy readout in mil or mm
• Real-time cross-probe cursor — continuous coordinate tracking across all layers on the canvas
• Customizable grid overlay — none, lines, dots, or crosshair modes; aligns to Gerber origin or bounding box
• Zoom controls — zoom in/out buttons, fit-to-view, zoom percentage input with scroll wheel support and expression evaluation
• Canvas flip / mirror view toggle for inspecting board from different perspectives
• Layer management panel — individual visibility eye icons, per-layer opacity sliders, global opacity control
• Automatic 32-color palette assignment per layer for clear visual distinction

Supported File Formats

• Gerber RS-274X (.gbr .ger .gtl .gbl .gts .gbs .gto .gbo .gtp .gbp .g1 .g2 .g3 .g4 .gp1 .gp2 .gp3 .gp4 .gm1 .gm2 .gm3 .gm4 .art .pho) — Full RS-274X aperture support for all standard Gerber extensions used by KiCad, Altium, Eagle, OrCAD, Allegro and more. Handles step-and-repeat, mirroring, and polarity operations.
• Allegro / PADS (.art .pho .p* .s* .m*) — Cadence Allegro artwork (.art) and PADS PCB Gerber output (.p* copper, .s* silkscreen, .m* mask). Common in advanced PCB design workflows.
• Excellon Drill (.drl .xln .txt .tap .npt .exc) — Comprehensive Excellon drill file parsing with tool table support, plated/non-plated hole detection, and slot routing commands.
• ZIP Archive (.zip) — Batch import multiple PCB files in a ZIP archive with automatic decompression and filtering of macOS metadata files.
• Gerber X2 / X3 with Attributes — Extended Gerber format support including X2 attributes and X3 meta-information for enhanced layer identification and smart naming.

Supported CAD Tools

KiCad, Altium Designer (Altium Protel), Autodesk Eagle, Cadence OrCAD, Cadence Allegro, DipTrace, gEDA, Siemens PADS (Mentor), Proteus PCB, Pulsonix, DesignSpark PCB, EasyEDA / LCSC, CircuitMaker, CircuitStudio, Target 3001!, Zuken CR-8000, Zuken BoardStation, Mentor Expedition PCB, P-CAD

How to Use

1. Drag & drop your Gerber files onto this page, or click the folder icon in the toolbar to open files.
2. Supported formats: Gerber RS-274X (.gbr .ger .gtl .gbl), Excellon drill (.drl .xln), ZIP archives, and more.
3. Use the layer panel on the right to toggle visibility, adjust opacity, and reorder layers.
4. Measure distances and angles with the measurement tool, toggle grid overlay, or flip the canvas for inspection.

Frequently Asked Questions

What is a Gerber file?

Gerber RS-274X is the industry-standard file format used in PCB manufacturing. It describes copper layers, solder mask, silkscreen, and drill data for printed circuit boards.

Is this Gerber viewer really free?

Yes, completely free with no registration, no upload to server, and no file size limits. All processing happens locally in your browser.

What CAD tools does it support?

19 PCB design tools including KiCad, Altium Designer, Autodesk Eagle, Cadence OrCAD/Allegro, DipTrace, gEDA, Siemens PADS, Proteus, Pulsonix, DesignSpark, EasyEDA, CircuitMaker, CircuitStudio, Target 3001!, Zuken CR-8000/BoardStation, Mentor Expedition, and P-CAD.

Can I view multiple layers at once?

Yes. Multi-layer overlay with independent opacity control, visibility toggle, and automatic color-coded layers makes it easy to inspect complex PCB designs.

Do you store or upload my files?

No. All data is processed locally in your browser using JavaScript. Your files never leave your device, ensuring complete privacy.