Compare

How Keely compares.

The Polar Loop with Keely is a way to get recovery, training load, stress, sleep, a VO₂ max and an age for your fitness without a subscription. These pages compare it with WHOOP, Oura, Garmin, Apple Watch, Amazfit, Ultrahuman and Polar’s own app, Polar Flow: what each costs, what each measures, and what each does that Keely doesn’t.

Updated October 5, 2026

Side by side

US prices, checked October 5, 2026. Each comparison has the details and its sources.

	Cost (US)	VO₂ max from	An age
Polar Loop with Keely	$199.99 once, with no subscription	Your walks and runs, against the Loop’s heart rate	Keely Age, from VO₂ max alone
WHOOP	From $199 a year: a required membership, band included	Your nights and activity; a GPS run or a lab test sharpens it	WHOOP Age, from nine measures (Peak and Life)
Oura Ring 5	$399 to $499, and $5.99 a month for all but three scores	A six-minute walking test, with a membership	Cardiovascular Age, with a membership
Garmin CIRQA	$199.99, with no subscription needed	A timed 15-minute walk or run	Fitness Age
Apple Watch	From $249, with no subscription	Outdoor walks, runs and hikes	Health Age, announced
Amazfit Helio Strap	$99.99 (Pro $199.99), with no subscription needed	Listed among its training metrics	Not listed
Ultrahuman Ring AIR	$349 on its global store; no subscription to see your data	Your nights and activity	Cardio Age and Ultra Age
Polar Flow	Free, for the same Loop	A five-minute test at rest	Not listed

The comparisons

How we write them

Facts come from the source. Everything about another product comes from its maker’s own pages, with the date we checked. Prices and features change, so check theirs before you buy.
Fair both ways. Each comparison says where the other product does more than Keely.
Names, not endorsements. We name other products only to compare them. Keely isn’t affiliated with or endorsed by any company named here.

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