Adafruit NeoPixel Ring 12 (#1643): Ø36.83 × Ø23.37 mm ring and LED positions — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/adafruit-neopixel-ring-12-1643/  (sheet CC BY 4.0)
Basis: Adafruit's EagleCAD board file for the NeoPixel Ring 12 and the NeoPixel Überguide ring page (3.6 mm total thickness).
Catalog version: 2026-10-20

Overall (mm): length 36.83, width 36.83, height 3.6
- Flat ring PCB: outer Ø36.830, bore Ø23.368, centred, board bottom at 0, LEDs facing up. Board thickness 1.6 is taken from Adafruit's Überguide note (1.6 PCB + 2 mm LEDs) and is not stated in the board file.
- 12 WS2812B LEDs, 5.0 × 5.0, standing 2.0 above the board (top at 3.6), centred on a Ø29.464 circle every 30°, LED 1 at (0, +14.732).
- No mounting holes: hold the ring by its outer edge, its bore or its back face.
- Not modelled: the wire/solder pads on the back and the breakaway-tab stubs on the rim.
- All dimensions are exact nominal millimetres, true size, with no tolerance added.

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Adafruit: NeoPixel Ring - 12 x 5050 RGB LED with Integrated Drivers (#1643) — web — Publisher's page; dimensions are facts — https://www.adafruit.com/product/1643
- Adafruit: Adafruit-NeoPixel-Ring repository — web — Publisher's page; dimensions are facts — https://github.com/adafruit/Adafruit-NeoPixel-Ring
- Adafruit Learning System: Adafruit NeoPixel Überguide: NeoPixel Rings — web — Publisher's page; dimensions are facts — https://learn.adafruit.com/adafruit-neopixel-uberguide/neopixel-rings

Free files (CC BY 4.0, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/adafruit-neopixel-ring-12-1643/index.json
API: https://xemstudio.com/api/geometry?object=adafruit-neopixel-ring-12-1643