WHOOP 4.0 with 12 Month Subscription - Wearable Health, Fitness & Activity Tracker Review (2026)

Who this wearable is for

WHOOP 4.0 is built for people who want to track recovery, sleep, and daily strain without wearing a traditional smartwatch, since the device has no screen at all and relies entirely on its companion phone app for data. The included 12 month membership means it works right out of the box without a separate signup decision on day one, which suits someone testing whether ongoing recovery tracking is worth the cost. Its Any-Wear design, which allows accurate readings from the torso, waist, or calf in addition to the wrist, makes it a fit for athletes in sports where a wrist strap gets in the way. It is a poor fit for anyone who wants an at-a-glance screen for time, notifications, or workout stats without pulling out a phone.

Hardware and sensors

The sensor itself measures about 36 by 25 by 10 millimeters and weighs roughly 11 grams on its own, or about 28.5 grams with the strap attached, making it noticeably smaller and lighter than most screened fitness watches. It carries an IP68 water resistance rating, rated for depths up to 10 meters for up to two hours, which covers swimming and showering without concern. Onboard sensors include an optical heart rate monitor, a blood oxygen sensor, a skin temperature sensor, an accelerometer, and a gyroscope, feeding the recovery and strain scores the platform is built around. Charging uses a slide-on battery pack that clips over the sensor so it can keep collecting data while charging, with battery life rated at up to five days between charges.

What the membership tracks

The bundled 12 month membership unlocks WHOOP's core metrics, including sleep stages, heart rate variability, respiratory rate, skin temperature trends, a daily recovery score, and a strain score that estimates cardiovascular load across the day. A Sleep Coach feature can deliver gentle haptic alerts to wake the wearer at an optimal point in their sleep cycle rather than at a fixed alarm time. Because there is no screen, all of this data is reviewed through the phone app rather than glanced at on the wrist, which some buyers will find limiting and others will prefer, since it removes the temptation to check notifications mid-workout.

Trade-offs against rival wearables

Against ring-style trackers like the Oura Ring or screened trackers like the Fitbit Charge or Garmin vivosmart, WHOOP's main trade-off is the ongoing membership model, since the hardware itself does relatively little without an active subscription once the included period ends. Its Any-Wear flexibility to move the sensor off the wrist is a genuine differentiator few competitors offer, and its focus on recovery and strain scoring is more specialized than general step-counting wearables. WHOOP has since released a newer 5.0 generation with longer battery life, so buyers should weigh whether the 4.0's lower price offsets its shorter roughly five-day battery life compared with the newer model's up to fourteen days.

Verdict

WHOOP 4.0 delivers detailed recovery, sleep, and strain tracking in a small, screenless sensor that can be worn in more places than just the wrist, backed by a 12 month membership included in this bundle. It is best suited to people who genuinely want to act on daily recovery data through an app rather than glance at a watch face. The membership requirement after the included year is the main long-term cost to weigh, and buyers deciding between generations should also consider that the newer 5.0 model offers substantially longer battery life for those who plan to keep the device for years.

Frequently asked questions