Your Whoop can act like a chest strap. Buried in the app is a setting called Heart Rate Broadcast, and it is the one place the strap’s continuous, live signal is available to software and hardware you choose. Here is how to turn it on, what can read it, and the two quirks that generate most of the confusion.
How do I turn it on?
Open the WHOOP app, go to your device’s settings, and toggle Heart Rate Broadcast on. WHOOP’s support article adds one detail people miss: make sure your phone is connected to the strap when you flip the toggle, so the setting actually takes effect. The menu wording has shifted across app versions — look for it under the strap or device settings screen.
What can read the broadcast?
Anything that speaks the standard Bluetooth heart-rate profile — the same open protocol chest straps have used for years. In practice that means gym equipment, bike computers, rowing ergs, and training apps: WHOOP’s own compatibility list includes the likes of Peloton, Zwift, Wahoo computers, and Concept2 ergs. If a device or app can pair with a chest strap, it can read a broadcasting Whoop.
One boundary: the broadcast is Bluetooth only. The strap does not transmit ANT+, so older devices that only speak that protocol are out.
Why did it turn itself off?
This is the quirk that fills support threads. WHOOP’s documentation says it plainly: HR Broadcast may automatically toggle off after a software or firmware update. If a receiver that worked last week suddenly finds no signal, check the toggle first — an app update has usually reset it. After any Whoop app or firmware update, it is worth the five seconds to look.
Can it recover data I missed?
No. WHOOP describes the broadcast as a real-time stream with no backfilling capabilities. If the receiving device is out of Bluetooth range, or the connection drops, that stretch is simply absent on the receiver — the strap does not send it later. Whatever listens to the broadcast has to be there while it happens.
Should I turn Heart Rate Broadcast on?
If you own a Whoop and anything with a heart-rate readout — a bike computer, an erg, a training app — the broadcast is free signal you already paid for. Turn it on, and get in the habit of re-checking it after updates. It is also the channel brainful is built on: the b-score app for Whoop straps listens to the same broadcast and puts a b-score (0–100) on each calendar event — what each hour was actually worth — live on the phone, with no pairing and no account. Whatever you point at it, the rule is the same: the broadcast is live-only, so the listener has to be running while the day happens.
Source: WHOOP Support, “Heart Rate Broadcast” — the enable steps, the Bluetooth-only note, the automatic toggle-off warning, and the “real-time stream with no backfilling capabilities” description are WHOOP’s own.