b.ring G2 vs Pro: Which Smart Ring and Size to Choose
b.ring G2 and b.ring Pro track the same core health data — sleep, heart rate, HRV, blood oxygen (SpO2), stress and activity — with no subscription on either. The differences are material, weight, skin temperature and charging. Here is how to choose, and how to get the right size.
G2 or Pro: the key differences
| b.ring G2 | b.ring Pro | |
|---|---|---|
| Material | Stainless steel | Titanium |
| Colors | Black, Silver | Black, Silver, Rose gold |
| Weight / thickness / width | 2.9 g / 2.7 mm / 8.0 mm | 2.7 g / 2.55 mm / 7.0 mm |
| Skin temperature trends | — | Yes |
| Charging | Charging case, about 90 min | Wireless charging dock, about 90 min |
| Battery | Up to 7 days | Up to 7 days |
| Water resistance | IP68 + 5ATM | IP68 + 5ATM |
| Sizes | US 7–12 | US 7–12 |
| Warranty | 1 year | 1 year |
Choose b.ring G2 if…
- You want full sleep, heart rate, HRV and stress tracking at a lower price
- You prefer a stainless steel finish
Choose b.ring Pro if…
- You want skin temperature trends in addition to everything G2 tracks
- You want the thinnest, lightest b.ring for wearing day and night
- You prefer simply placing the ring on a wireless dock to charge
How to find your size
- Order the b.ring Sizing Kit ($4.99). It includes try-on sizers for US 7 to US 12 (inner diameter 17.5 mm to 21.6 mm).
- Wear a sizer on the finger you plan to use, ideally for a full day including sleep.
- Pick the size that feels snug but comfortable and slides over your knuckle.
Smart rings fit differently from regular jewelry rings, and sizes vary between brands, so we recommend sizing with the kit even if you know your usual ring size. Ring sizes can't be exchanged after purchase; unopened products can be returned within 14 days of delivery under our Refund Policy.
Frequently asked questions
Do G2 and Pro use the same app?
Yes. Both use the free b.ring app for iPhone and Android, with no subscription.
Can I swim or shower with either ring?
Yes. Both are rated IP68 and 5ATM.
Which finger should I wear it on?
Choose the finger where the ring fits snugly and comfortably, and size for that finger with the Sizing Kit.