# Adafruit QT Py, ItsyBitsy, Trinket, GEMMA and Trinkey boards > What are the QT Py and ItsyBitsy board dimensions? - Category: Electronics › Microcontroller boards - Kind: Modern device - Basis: Adafruit CAD (MIT): QT Py 21.8 × 17.8 mm (0.86 × 0.7 in), ItsyBitsy 36 × 18 mm (1.4 × 0.7 in), Trinket M0 27 × 15.3 mm, GEMMA M0 Ø27.9 mm - Page: https://xemstudio.com/objects/adafruit-qt-py-itsybitsy-trinket/ · JSON: https://xemstudio.com/api/geometry?object=adafruit-qt-py-itsybitsy-trinket · Plain text: https://xemstudio.com/objects/adafruit-qt-py-itsybitsy-trinket/sheet.txt - License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses ## Notes - QT Py (every variant: SAMD21, RP2040, ESP32-S2/S3/C3/PICO): 21.8 × 17.8 mm, USB-C at one end, STEMMA QT JST SH at the other, no mounting holes; cases hold it by the edge with a 0.3 mm lip. - ItsyBitsy: 36 × 18 mm, 28 pins on 2.54 mm pitch, no holes. Trinket M0: 27 × 15.3 mm with two Ø2.5 holes. GEMMA M0: Ø27.9 mm round with three large sew pads. - Trinkeys are USB-A plug boards (~34 × 18 mm with the plug); KB2040 is a Pro Micro footprint (33 × 18 mm, 24 pins). ## Sizes | product | bbox_l_mm | bbox_w_mm | bbox_h_mm | |---|---|---|---| | 4600 QT Py | 21.8 | 17.8 | 6.3 | | 4900 QTPy RP2040 | 21.8 | 17.8 | 5.9 | | 5426 QT Py ESP32-S3 | 21.8 | 17.8 | 5.9 | | 5395 QT Py ESP32 PICO | 21.7 | 17.8 | 5.6 | | 5325 QTPy ESP32S2 | 21.7 | 17.8 | 5.9 | | 5405 QTPy ESP32 C3 | 21.7 | 17.8 | 5.9 | | 3800 ItsyBitsy M4 | 36.0 | 17.8 | 4.3 | | 4888 ItsyBitsy RP2040 | 36.1 | 17.8 | 4.3 | | 4481 ItsyBitsy nRF52840 | 36.2 | 17.8 | 5.7 | | 5889 ItsyBitsy ESP32 | 36.1 | 17.8 | 7.4 | | 3500 Trinket M0 | 27.2 | 15.2 | 3.6 | | 3501 GEMMA M0 | 28.0 | 27.9 | 6.4 | | 5302 KB2040 | 34.2 | 17.8 | 4.8 | | 4870 Neo Trinkey | 31.7 | 12.1 | 3.9 | | 4964 Rotary Trinkey | 32.4 | 30.4 | 16.5 | | 5020 NeoKey Trinkey | 31.6 | 19.2 | 16.5 | | 5056 Trinkey QT2040 | 38.1 | 19.7 | 5.5 | | 5953 Pixel Trinkey | 40.2 | 15.2 | 12.0 | ## Where the files are - Adafruit (official): [Adafruit_CAD_Parts: STEP, Fusion 360 and STL for Adafruit products](https://github.com/adafruit/Adafruit_CAD_Parts) — STEP, F3D, STL — MIT ## Free STEP/STL (18 parts, MIT License (Adafruit_CAD_Parts), Adafruit Industries) Index: https://xemstudio.com/files/adafruit/adafruit-qt-py-itsybitsy-trinket/index.json - 4600-qt-py: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4600%20QT%20Py/4600%20QTPy.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4600%20QT%20Py/4600%20QTPy.step.stl) — Adafruit #4600 QT Py; bbox 21.8 × 17.8 × 6.3 mm; 2.3 MB on GitHub - 4900-qtpy-rp2040: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4900%20QTPy%20RP2040/4900%20QTPY-RP2040.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4900%20QTPy%20RP2040/4900%20QTPY-RP2040.stl) — Adafruit #4900 QTPy RP2040; bbox 21.8 × 17.8 × 5.9 mm; 1.9 MB on GitHub - 5426-qt-py-esp32-s3: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5426%20QT%20Py%20ESP32-S3/5426%20QT%20Py%20ESP32-S3.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5426%20QT%20Py%20ESP32-S3/5426%20QT%20Py%20ESP32-S3.stl) — Adafruit #5426 QT Py ESP32-S3; bbox 21.8 × 17.8 × 5.9 mm; 1.4 MB on GitHub - 5395-qt-py-esp32-pico: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5395%20QT%20Py%20ESP32%20PICO/5395%20QT%20Py%20ESP32%20PICO.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5395%20QT%20Py%20ESP32%20PICO/5395%20QT%20Py%20ESP32%20PICO.stl) — Adafruit #5395 QT Py ESP32 PICO; bbox 21.7 × 17.8 × 5.6 mm; 2.1 MB on GitHub - 5325-qtpy-esp32s2: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5325%20QTPy%20ESP32S2/5325%20QTPy%20ESP32S2.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5325%20QTPy%20ESP32S2/5325%20QTPy%20ESP32S2.stl) — Adafruit #5325 QTPy ESP32S2; bbox 21.7 × 17.8 × 5.9 mm; 2.7 MB on GitHub - 5405-qtpy-esp32-c3: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5405%20QTPy%20ESP32%20C3/5405%20QTPy%20ESP32%20C3.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5405%20QTPy%20ESP32%20C3/5405%20QTPy%20ESP32%20C3.stl) — Adafruit #5405 QTPy ESP32 C3; bbox 21.7 × 17.8 × 5.9 mm; 1.9 MB on GitHub - 3800-itsybitsy-m4: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/3800%20ItsyBitsy%20M4/3800-ItsyBitsy-M4.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/3800%20ItsyBitsy%20M4/3800-ItsyBitsy-M4.stl) — Adafruit #3800 ItsyBitsy M4; bbox 36.0 × 17.8 × 4.3 mm; 2.6 MB on GitHub - 4888-itsybitsy-rp2040: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4888%20ItsyBitsy%20RP2040/4888%20ItsyBitsy%20RP2040.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4888%20ItsyBitsy%20RP2040/4888%20ItsyBitsy%20RP2040.stl) — Adafruit #4888 ItsyBitsy RP2040; bbox 36.1 × 17.8 × 4.3 mm; 1.9 MB on GitHub - 4481-itsybitsy-nrf52840: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4481%20ItsyBitsy%20nRF52840/4481%20ItsyBitsy%20nRF52840.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4481%20ItsyBitsy%20nRF52840/4481%20ItsyBitsy%20nRF52840.stl) — Adafruit #4481 ItsyBitsy nRF52840; bbox 36.2 × 17.8 × 5.7 mm; 1.9 MB on GitHub - 5889-itsybitsy-esp32: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5889%20ItsyBitsy%20ESP32/5889%20ItsyBitsy%20ESP32.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5889%20ItsyBitsy%20ESP32/5889%20ItsyBitsy%20ESP32.stl) — Adafruit #5889 ItsyBitsy ESP32; bbox 36.1 × 17.8 × 7.4 mm; 3.2 MB on GitHub - 3500-trinket-m0: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/3500%20Trinket%20M0/Trinket%20M0.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/3500%20Trinket%20M0/Trinket%20M0.stl) — Adafruit #3500 Trinket M0; bbox 27.2 × 15.2 × 3.6 mm; 2.0 MB on GitHub - 3501-gemma-m0: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/3501%20GEMMA%20M0/3501%20GEMMA%20M0.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/3501%20GEMMA%20M0/3501%20GEMMA%20M0.stl) — Adafruit #3501 GEMMA M0; bbox 28.0 × 27.9 × 6.4 mm; 2.6 MB on GitHub - 5302-kb2040: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5302%20KB2040/5302%20KB2040.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5302%20KB2040/5302%20KB2040.stl) — Adafruit #5302 KB2040; bbox 34.2 × 17.8 × 4.8 mm; 2.2 MB on GitHub - 4870-neo-trinkey: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4870%20Neo%20Trinkey/4870%20Neo%20Trinkey.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4870%20Neo%20Trinkey/4870%20Neo%20Trinkey.stl) — Adafruit #4870 Neo Trinkey; bbox 31.7 × 12.1 × 3.9 mm; 1.2 MB on GitHub - 4964-rotary-trinkey: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4964%20Rotary%20Trinkey/4964%20Rotary%20Trinkey.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/4964%20Rotary%20Trinkey/4964%20Rotary%20Trinkey.stl) — Adafruit #4964 Rotary Trinkey; bbox 32.4 × 30.4 × 16.5 mm; 1.5 MB on GitHub - 5020-neokey-trinkey: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5020%20NeoKey%20Trinkey/5020%20NeoKey%20Trinkey.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5020%20NeoKey%20Trinkey/5020%20NeoKey%20Trinkey.stl) — Adafruit #5020 NeoKey Trinkey; bbox 31.6 × 19.2 × 16.5 mm; 0.9 MB on GitHub - 5056-trinkey-qt2040: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5056%20Trinkey%20QT2040/5056%20Trinkey%20QT2040.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5056%20Trinkey%20QT2040/5056%20Trinkey%20QT2040.stl) — Adafruit #5056 Trinkey QT2040; bbox 38.1 × 19.7 × 5.5 mm; 0.9 MB on GitHub - 5953-pixel-trinkey: [STEP](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5953%20Pixel%20Trinkey/5953%20Pixel%20Trinkey.step) · [STL](https://raw.githubusercontent.com/adafruit/Adafruit_CAD_Parts/main/5953%20Pixel%20Trinkey/5953%20Pixel%20Trinkey.stl) — Adafruit #5953 Pixel Trinkey; bbox 40.2 × 15.2 × 12.0 mm; 2.5 MB on GitHub ## Questions **What are QT Py dimensions?** 21.8 × 17.8 mm, about 5 mm tall with the USB-C and STEMMA QT connectors; no mounting holes, same outline as the Seeed XIAO. **Does the QT Py fit XIAO cases?** The outline is the same 21 × 17.8 mm class and the castellated pins match; the STEMMA QT connector on the QT Py adds 1.5 mm at the back end, so check that side. **What are ItsyBitsy dimensions?** 36 × 18 mm, 2.54 mm headers down both long edges, no mounting holes. ## Fits with - [Seeed Studio XIAO (all variants)](https://xemstudio.com/objects/seeed-xiao/) - [Adafruit Feather boards and FeatherWings](https://xemstudio.com/objects/adafruit-feather-boards/) - [2.54 mm pin headers, 1×2 to 2×20, vertical and right-angle](https://xemstudio.com/objects/pin-headers-2.54mm/) - [USB-C receptacle (16/24-pin, mid-mount)](https://xemstudio.com/objects/usb-c-receptacle/)