# Polar Loop with Keely, or Oura.

> https://meetkeely.com/compare/oura · Updated 2026-09-28 · Keely, by Metrica Fit LLC

**Both read your night and score how ready you are each morning.** An Oura Ring 5 costs $399 to $499, and a membership, $5.99 a month or $69.99 a year, unlocks everything beyond its three daily scores. A Polar Loop is $199.99 once, and Keely is free. Oura is a ring and measures blood oxygen; Keely adds a training Load with a daily target and live stress, and publishes every formula.

## At a glance

| | Polar Loop with Keely | Oura Ring 5 |
|---|---|---|
| Price (US) | $199.99 for the Loop, once. Keely is free | $399 to $499 (Ring 4 is still sold from $349) |
| Membership | None | $5.99 a month or $69.99 a year. Without it: the Readiness, Sleep and Activity scores only |
| Worn as | A band on the wrist | A ring |
| Morning score | Recovery, 0–100 %: HRV, resting heart rate, sleep, breathing rate and skin temperature | Readiness, 0–100: resting heart rate, HRV balance, temperature, sleep and activity |
| Effort | Load: points per minute by heart-rate zone, no ceiling, with a daily target and Balance | Activity score, 0–100 |
| Stress | Live, 0–100, scored only while you’re still | Daytime Stress in four zones (stressed, engaged, relaxed, restored), with a membership |
| Sleep | Stages from the Loop, need (goal, debt and a hard day), consistency and a lights-out time | Sleep score, 0–100, with stages; detailed sleep with a membership |
| Formulas | Every input, weight and constant is published | Contributors are described; Oura calls its algorithms proprietary |
| Sensors | Optical heart rate, accelerometer, skin temperature | Adds blood oxygen |
| Battery, by the maker | Up to 8 days (Polar’s figure, with Polar Flow) | 6 to 9 days (Ring 4: 5 to 8) |
| Water | WR30: swimming, not diving | Water-resistant to 100 m |
| Your data | Raw heart data stays on your iPhone; your account backs up daily summaries | Stored in your Oura account; the API needs a membership |

Facts about Oura come from Oura’s own pages, checked September 28, 2026. This page compares cost, scores and data; it doesn’t test sensor accuracy.

## Cost over two years

At today’s US prices, with the yearly membership and no discounts:

| | First year | Two years |
|---|---|---|
| Polar Loop with Keely | $199.99 | $199.99 |
| Oura Ring 5 with membership | $468.99 to $568.99 | $538.98 to $638.98 |
| Oura Ring 4 with membership | $418.99 | $488.98 |

Oura includes one month of membership with a new ring, so its first year can come in slightly lower.

## Where Oura does more

- **A ring.** Some people find a ring easier to wear every night than a band.
- **Blood oxygen**, plus features Keely doesn’t have: Cardiovascular Age, Cardio Capacity (a VO₂ max estimate), Resilience, and Health Radar in some countries.
- **Water resistance to 100 m**, against the Loop’s 30.
- **Your data, out.** An API with a membership. Keely doesn’t export yet.

## Where Keely is different

- **No membership.** You buy the Loop once, and Keely is free. Oura’s scores beyond Readiness, Sleep and Activity need a membership.
- **Training Load with a target.** Keely counts every minute by its heart-rate zone and sets a range for the day from your Recovery and your last four weeks. See [Load](https://meetkeely.com/load).
- **Stress as a number, live.** From 0 to 100 while Keely is open, and never scored while you move. See [Stress](https://meetkeely.com/stress).
- **Every formula is public.** On the [methodology page](https://meetkeely.com/methodology).
- **Your raw heart data stays on your iPhone.**

## Frequently asked questions

### Is the Polar Loop with Keely an Oura alternative without a membership?

Yes. You buy the Loop once, and Keely gives you a morning Recovery score, a Load target, live stress and sleep against your need, free. Oura’s membership is $5.99 a month or $69.99 a year.

### Is Keely’s Recovery like Oura’s Readiness?

Both score last night against your own normal from HRV, resting heart rate, sleep and temperature, from 0 to 100. They’re different calculations, so the numbers won’t match. Keely’s is on its [Recovery page](https://meetkeely.com/recovery).

### Can I use an Oura Ring with Keely?

No. Keely works with the Polar Loop.

## Sources

- Oura Ring 5: [Oura’s store](https://ouraring.com/store/rings/oura-ring-5) and [Discover Oura Ring 5](https://support.ouraring.com/hc/en-us/articles/50997181300243-Discover-Oura-Ring-5). Ring 4: [Oura’s store](https://ouraring.com/store/rings/oura-ring-4/silver).
- Membership: [Oura Membership](https://support.ouraring.com/hc/en-us/articles/4409086524819-Oura-Membership) (updated September 8, 2026).
- Scores: [Readiness](https://support.ouraring.com/hc/en-us/articles/360025589793-Readiness-Score), [Sleep](https://support.ouraring.com/hc/en-us/articles/360025445574-Sleep-Score), [Activity](https://support.ouraring.com/hc/en-us/articles/360025577993-Activity-Score) and [Daytime Stress](https://support.ouraring.com/hc/en-us/articles/21205822135315-Daytime-Stress).
- Polar Loop price: [Polar’s US store](https://www.polar.com/us-en/loop). Specifications: [Polar Loop user manual](https://support.polar.com/e_manuals/polar-loop/polar-loop-user-manual-english/technical-specifications.htm).

All checked September 28, 2026. Prices and features change, so check Oura’s before you buy. Oura is a trademark of Oura Health Oy; Keely isn’t affiliated with or endorsed by Oura or Polar.

## Keep reading

- [WHOOP](https://meetkeely.com/compare/whoop): The Polar Loop with the free Keely app, compared with WHOOP: cost, Recovery, Strain and Load, stress, sleep and your data. Checked September 28, 2026.
- [Polar Flow](https://meetkeely.com/compare/polar-flow): Two free apps for the same band. How Keely compares with Polar Flow for the Polar Loop: Recovery and Nightly Recharge, Load, stress, sleep, data and switching.
- [Sleep](https://meetkeely.com/sleep): Keely shows your night from the Polar Loop as a story: stages with heart rate, HRV and stress, time asleep against your need, consistency and a lights-out time.

Keely is coming to the App Store for iPhone (iOS 26 or later). Need a Polar Loop? https://meetkeely.com/loop (an affiliate link: as an Amazon Associate, Metrica Fit earns from qualifying purchases).