Best Smart Rings · head-to-head

Ultrahuman Ring AIR vs Luna Ring Gen 2

A sourced, side-by-side comparison. Luna Ring Gen 2 is cheaper at $300. Every spec and price links to its source.

Which is better: the Ultrahuman Ring AIR or Luna Ring Gen 2?

On the specs we track, they're closely matched. The Luna Ring Gen 2 is the cheaper at $300.

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Full spec sheet

marks the stronger figure where "more" — or "less", for price and weight — is unambiguously better.

Spec Ultrahuman Ring AIR Luna Ring Gen 2
US price $349 $300
BrandUltrahumanNoise
Released2023-062025-07
Material Titanium outer shell with tungsten carbide carbon coating; medical-grade hypoallergenic inner layer Fighter jet-grade titanium with PVD coating and non-allergenic inner molding
Weight (g) 2.4-3.6 3-5
Battery days 6 6
Spo2 Yes Yes
Temperature sensor Yes Yes
Ecg No No
Subscription required No No
Water resistance (m) 100 50

Sources — Ultrahuman Ring AIR: ultrahuman.com (verified 2026-06-15). Luna Ring Gen 2: lunazone.com (verified 2026-06-15).

What's the difference between the Ultrahuman Ring AIR and Luna Ring Gen 2?

Where the two actually differ on the specs we track (3 of 8). Matching specs are omitted.

  • Material: Ultrahuman Ring AIR Titanium outer shell with tungsten carbide carbon coating; medical-grade hypoallergenic inner layer vs Luna Ring Gen 2 Fighter jet-grade titanium with PVD coating and non-allergenic inner molding
  • Weight (g): Ultrahuman Ring AIR 2.4-3.6 vs Luna Ring Gen 2 3-5
  • Water resistance (m): Ultrahuman Ring AIR 100 vs Luna Ring Gen 2 50

What reviewers say

Sourced tester consensus for each — the "what people who used it think" layer, not just specs.

Ultrahuman Ring AIR

Two whitelisted testers (TechRadar, Digital Trends) each wore the Ring Air hands-on for a full month in August 2023 and agree it is exceptionally light, comfortable to wear 24/7, accurate against wrist wearables in side-by-side testing, and free of any subscription. Both also flag that it scratches within weeks of gym/daily wear and packs in a lot of data to comb through, though they split on how usable the app is. (2 sourced reviews, 2 lab-tested.)

Praised: Exceptionally light and comfortable to wear 24/7, including overnight; Health/sleep/heart-rate data tracks accurately vs wrist wearables in side-by-side testing; No monthly subscription fee, unlike Oura and Whoop.

Flagged: Titanium coating scratches within a few weeks of gym/daily wear; A lot of data to comb through; the app is data-dense; Expensive at $349.

Luna Ring Gen 2

No sourced tester review yet.

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