Whoop · Fitness Band
Whoop 4.0
The previous Whoop. Replaced by the 5.0 with longer battery and Healthspan.
$30/moWhoop →
Battery5 days
Water1 ATM
Weight30g
Sensors5
OS2 platforms
The Whoop 4.0 (2021) brought continuous HR + SpO₂ + skin-temp to the band format. Replaced in 2025 by the Whoop 5 with double the battery life and Healthspan / longevity scores. Still on the market for current members on legacy hardware.
Strengths
- Continuous HR sampling
- Battery pack swaps in place
- Whoop Coach AI included
Tradeoffs
- Replaced by Whoop 5
- No longevity / Healthspan tools
- Subscription required at $30/mo
Full specs
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Common questions
- How much does the Whoop 4.0 cost?
- The Whoop 4.0 has no separate hardware price — it comes with the Whoop membership at $30/mo.
- Does the Whoop 4.0 require a subscription?
- Yes. The Whoop 4.0 needs an active Whoop membership at $30/month — without it the device stops reporting your data.
- How long does the Whoop 4.0 battery last?
- About 5 days of typical use per charge. Heavy GPS use, an always-on display, and continuous sensing all pull that number down.
- Is the Whoop 4.0 waterproof?
- The Whoop 4.0 is rated 1 ATM (10m). Treat that as protection against rain, sweat, and handwashing rather than a swimming rating.
- Does the Whoop 4.0 work with iPhone and Android?
- It pairs with both iPhone and Android.
- Is the Whoop 4.0 still worth buying?
- The Whoop 4.0 came out in 2021 and Whoop has discontinued it, so new stock is limited and prices vary. Check it against the current fitness band lineup before buying.