Wearable Index
Oura · Ring

Ring 5

Shipping

The Oura Ring 5 is a $399 smart ring, shipping since 2026. The world's smallest smart ring — roughly 40% smaller, week-long battery and new blood-pressure signals.

Compare this device
Oura Ring 5 — ring worn on the finger
Image sourceHarvey Norman

Generations

GenerationYearStatusPriceWeight
Ring 5 2026 Shipping $399 From 2 g depending on size
Ring 4 2024 Shipping $349 3.3–5.2 g
Ring Gen3 2022 Discontinued $299 4–6 g

Specifications by generation

Oura Ring 5
Image sourceHarvey Norman

Ring 5

2026Shipping

The world's smallest smart ring — roughly 40% smaller, week-long battery and new blood-pressure signals.

Category
Ring
Worn
Finger
Release
2026
Price
$399
Weight
From 2 g depending on size
Sensors & hardware
  • Biometric PPG heart rate (next-gen)Skin temperatureBlood oxygen (SpO₂)Blood pressure (signals)
  • Motion Accelerometer

Developer access

  • Oura API v2 public stable
    • Authorized sleep, activity, readiness and other documented user data
    • HTTPS / OAuth 2.0

    Oura account and OAuth application required; ten-user default limit; approval required for wider release. V1 removed January 22, 2024.

Documentation
public
Vendor servers
required

The documented developer API reads Oura cloud data with OAuth consent. This classification applies to the cloud API, not every possible ring function.

Not yet verified: app distribution and hardware and software openness.

Openness, servers & distribution
hardware

Unknown; no hardware-design publication was verified in the reviewed sources.

firmware

Unknown; the reviewed documentation does not establish source availability or licensing.

companion apps

Unknown; the reviewed documentation does not establish source availability or licensing.

SDK

Unknown; the reviewed documentation does not establish source availability or licensing.

backend services

Unknown; the reviewed documentation does not establish source availability or licensing.

Direct / local access

Unknown; no direct/local API was verified in the reviewed documentation.

Third-party cloud

Oura cloud API; other required cloud services Unknown

App distribution

A phone companion app is not an app store; a third-party directory was not verified.

Oura Ring 4
Image sourceUbuy

Ring 4

2024Shipping

Titanium sleep & readiness ring with recessed Smart Sensing and a sleeker profile.

Category
Ring
Worn
Finger
Release
2024
Price
$349
Weight
3.3–5.2 g
Sensors & hardware
  • Biometric PPG heart rateSkin temperatureBlood oxygen (SpO₂)
  • Motion Accelerometer

Developer access

  • Oura API v2 public stable
    • Authorized sleep, activity, readiness and other documented user data
    • HTTPS / OAuth 2.0

    Oura account and OAuth application required; ten-user default limit; approval required for wider release. V1 removed January 22, 2024.

Documentation
public
Vendor servers
required

The documented developer API reads Oura cloud data with OAuth consent. This classification applies to the cloud API, not every possible ring function.

Not yet verified: app distribution and hardware and software openness.

Openness, servers & distribution
hardware

Unknown; no hardware-design publication was verified in the reviewed sources.

firmware

Unknown; the reviewed documentation does not establish source availability or licensing.

companion apps

Unknown; the reviewed documentation does not establish source availability or licensing.

SDK

Unknown; the reviewed documentation does not establish source availability or licensing.

backend services

Unknown; the reviewed documentation does not establish source availability or licensing.

Direct / local access

Unknown; no direct/local API was verified in the reviewed documentation.

Third-party cloud

Oura cloud API; other required cloud services Unknown

App distribution

A phone companion app is not an app store; a third-party directory was not verified.

Oura Ring Gen3
Image sourceInstacart

Ring Gen3

2022Discontinued

Third-gen titanium ring that introduced continuous daytime heart rate and SpO₂ sensing.

Category
Ring
Worn
Finger
Release
2022
Price
$299
Weight
4–6 g
Sensors & hardware
  • Biometric PPG heart rateSkin temperatureBlood oxygen (SpO₂)
  • Motion Accelerometer

Developer access

  • Oura API v2 public stable
    • Authorized sleep, activity, readiness and other documented user data
    • HTTPS / OAuth 2.0

    Oura account and OAuth application required; ten-user default limit; approval required for wider release. V1 removed January 22, 2024.

Documentation
public
Vendor servers
required

The documented developer API reads Oura cloud data with OAuth consent. This classification applies to the cloud API, not every possible ring function.

Not yet verified: app distribution and hardware and software openness.

Openness, servers & distribution
hardware

Unknown; no hardware-design publication was verified in the reviewed sources.

firmware

Unknown; the reviewed documentation does not establish source availability or licensing.

companion apps

Unknown; the reviewed documentation does not establish source availability or licensing.

SDK

Unknown; the reviewed documentation does not establish source availability or licensing.

backend services

Unknown; the reviewed documentation does not establish source availability or licensing.

Direct / local access

Unknown; no direct/local API was verified in the reviewed documentation.

Third-party cloud

Oura cloud API; other required cloud services Unknown

App distribution

A phone companion app is not an app store; a third-party directory was not verified.

Company & funding

Oura Inc.

Venture funded; proposed IPO postponed September 29, 2026. No completed IPO was verified.

Disclosed funding
≈ USD 1.5Bcompany-published total · as of 2025-10-14

Company-published cumulative financing; equity/venture financing, debt/grant breakdown not specified. Historical October 2025 company-published total; not recomputed for later financing. The SEC separately discloses February 2026 Series E participation; no proceeds from the postponed IPO or secondary share sales are added.

Latest disclosed valuation
≈ USD 11B2025-10-14 · October 2025 financing · basis unspecified

Last verified private financing valuation; the 2026 proposed IPO share price is not substituted for a company valuation.

Disclosed rounds
2known minimum

Among makers in the index

Disclosed funding of the 32 makers in the index that publish a total, on a log scale in USD. Other currencies are placed at approximate rates; totals differ in date and coverage. Oura sits above 31 of the other 31.

Rounds

  1. 2025-10-14announced

    Series EOver USD 900M

    Led by Fidelity Management & Research Company

    With ICONIQ, Whale Rock and Atreides

    Equity / venture financing

    Initial financing announced in October 2025; SEC dates the initial Series E issuance to September 2025. February 2026 participation is tracked as an extension, not a new round; exact revised round total Unknown.

    Valuation ≈ USD 11B · basis unspecified

    Last verified private financing valuation; the 2026 proposed IPO share price is not substituted for a company valuation.

    1. 2026-02

      Series E extension≈ USD 10M

      Disclosed 2026-09-21

      With FMR LLC-affiliated entity

      Equity extension participation; same financing round · lead not disclosed

      SEC filing discloses approximately $10M invested in February 2026 at the existing Series E share price; this is not the total round and is not added to the dated October company total.

      Valuation not disclosed

      Same share price disclosed; no company valuation is inferred from it.

  2. 2024-12-19

    Series DUSD 200M

    With Fidelity Management & Research Company and Dexcom

    Equity / venture financing · lead not disclosed

    Not a cumulative company total.

    Valuation USD 5.2B · basis unspecified

    Company-announced valuation; pre/post-money basis not specified.

Historical valuations

  1. 2024-12-19

    Series DUSD 5.2B

    basis unspecified

    Company-announced valuation; pre/post-money basis not specified.

Company

Oura Inc. became the Delaware parent on March 31, 2026; Oura Health Oy is its wholly owned Finnish subsidiary and predecessor. The share swap preserved shareholder economic interests.

Brands: Oura, ŌURA

Investors on record

InvestorRoleRound
Fidelity Management & Research CompanyLeadOctober 2025 financing
ICONIQParticipantOctober 2025 financing
DexcomParticipantSeries D

Compare

oura.com All 124 devices

Independent index — figures are approximate and editorial, not official spec sheets. Methodology. Last reviewed 2026-10-31.