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+# Keychron K3 - Hardware Design Files
+
+> Ultra-slim 75% wireless mechanical keyboard with Bluetooth 5.1, USB-C wired mode, and support for macOS and Windows.
+
+**Product page:** [Keychron K3 Wireless Mechanical Keyboard](https://www.keychron.com/products/keychron-k3-wireless-mechanical-keyboard)
+
+![Keychron K3](https://www.keychron.com/cdn/shop/products/Keychron-K3-ultra-slim-wireless-mechanical-keyboard--5.jpg?v=1634644048)
+
+## Specifications
+
+| Spec | Detail |
+|---|---|
+| Layout | 75% |
+| Number of Keys | 84 |
+| Profile | Low-profile |
+| Switch Type | Low Profile Gateron Mechanical / Low Profile Keychron Optical (Hot-swappable) |
+| Backlight | White backlight / RGB backlight |
+| Connectivity | Bluetooth 5.1 / USB-C wired |
+| Hot-swappable | Available on the low profile Keychron Optical version |
+| Compatible System | macOS / Windows |
+
+## Included Files
+
+| File | Description |
+|---|---|
+| `K3-JP-Full-Model.stp` | Japan(JIS) layout full keyboard 3D CAD model |
+| `K3-JP-PCB-20221212.dwg` | Japan(JIS) layout PCB 2D CAD drawing |
+| `K3-UK-Full-Model.stp` | UK(ISO) full keyboard 3D CAD model |
+| `K3-UK-PCB-20221208.dwg` | UK(ISO) layout PCB 2D CAD drawing |
+| `K3-US-Full-Model.stp` | US full keyboard 3D CAD model |
+| `K3-US-PCB-20220926.dwg` | US PCB 2D CAD drawing |
+| `K3-US:UK:JP-Aluminum-Plate-20221025.dwg` | Shared US / UK / JP aluminum plate 2D CAD drawing |
+| `K3_JP_Bottom_Case.stp` | Japan(JIS) layout bottom case 3D CAD model |
+| `K3_JP_Top_Case.stp` | Japan(JIS) layout top case 3D CAD model |
+| `K3_UK_Bottom_Case.stp` | UK(ISO) layout bottom case 3D CAD model |
+| `K3_UK_Top_Case.stp` | UK(ISO) layout top case 3D CAD model |
+| `K3_US_Bottom_Case.stp` | US bottom case 3D CAD model |
+| `K3_US_Top_Case.stp` | US top case 3D CAD model |
+
+## Downloads
+
+> **Download note:** If a download link does not respond, copy the link and paste it directly into your browser's address bar. All links below are hosted on Keychron's official server and are safe to use.
+
+| File | Download Link |
+|---|---|
+| `K3-JP-Full-Model.stp` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3-JP-Full-Model.stp |
+| `K3-JP-PCB-20221212.dwg` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3-JP-PCB-20221212.dwg |
+| `K3-UK-Full-Model.stp` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3-UK-Full-Model.stp |
+| `K3-UK-PCB-20221208.dwg` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3-UK-PCB-20221208.dwg |
+| `K3-US-Full-Model.stp` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3-US-Full-Model.stp |
+| `K3-US-PCB-20220926.dwg` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3-US-PCB-20220926.dwg |
+| `K3-US:UK:JP-Aluminum-Plate-20221025.dwg` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3-US%3AUK%3AJP-Aluminum-Plate-20221025.dwg |
+| `K3_JP_Bottom_Case.stp` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3_JP_Bottom_Case.stp |
+| `K3_JP_Top_Case.stp` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3_JP_Top_Case.stp |
+| `K3_UK_Bottom_Case.stp` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3_UK_Bottom_Case.stp |
+| `K3_UK_Top_Case.stp` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3_UK_Top_Case.stp |
+| `K3_US_Bottom_Case.stp` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3_US_Bottom_Case.stp |
+| `K3_US_Top_Case.stp` | http://www.keychron.co:34568/keychron-github-assets/Keychron-Keyboards-Hardware-Design/K-Series/K3/K3_US_Top_Case.stp |
+
+## Opening the Files
+
+| Format | Free Software | Commercial Software |
+|---|---|---|
+| `.stp` | FreeCAD, Onshape | Fusion 360, SolidWorks |
+| `.dwg` | LibreCAD (limited), QCAD | AutoCAD, DraftSight |
+
+## Links
+
+- [Main Repository](https://github.com/Keychron/Keychron-Keyboards-Hardware-Design)
+
+## License
+
+This project is **source-available**. Personal and educational use is allowed, and commercial use is allowed for original compatible accessories within the limits of the license.
+
+**You may not use these files to copy, manufacture, sell, or distribute Keychron keyboards or mice, or substantially similar products, and you may not use Keychron trademarks as your own branding.**
+
+See the [LICENSE](../../LICENSE) for full terms.
diff --git a/README.md b/README.md
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--- a/README.md
+++ b/README.md
@@ -15,6 +15,7 @@ Study real CAD. Remix plates and cases. Design compatible accessories. Learn fro
 
 ## Latest Updates
 
+- **2026-05-19:** Added K3 files.
 - **2026-05-18:** Added V3 Ultra 8K files.
 - **2026-05-14:** Added K4 QMK files.
 - **2026-05-08:** Added BM25 and more K3 Pro files.