Sleep bracelet that tracks your night and responds while you sleep

This sleep bracelet tracks sleep stages and disruptions as you sleep, then responds in the moment. Raizz does not just track sleep, it actively improves it through real-time closed-loop vibrations.

Get Early Access
Raizz responds on your wrist while you sleep
Closed-loop vibrations adapt to your sleep state
30% higher self-rated sleep quality in Raizz results
Vibration varies by stage and your pattern
Technique studied in peer-reviewed vibration research

Raizz results

Raizz reports clear improvements you can map to real nights.

These outcomes summarize Raizz’s published results. Sleep-stage vibration research is covered separately below, so evidence types stay clear.

↓25%
time to sleep

Raizz reports 25% less time to fall asleep, aligning with the idea that pre-bed calming plus night-time support can reduce long settling periods.

↑30%
sleep quality

Raizz reports 30% higher overall self-rated sleep quality, which reflects how rested people feel, not only what a graph says.

↑2x
deep-sleep signals

Raizz reports 2x stronger biological indicators of deep sleep, using objective signals rather than only morning surveys.

Mechanism

How does Raizz turn a sleep monitor bracelet into real-time sleep support?

Raizz detects when you fall asleep and estimates sleep stages through the night. This sleep monitor bracelet then uses closed-loop vibration to respond before small arousals become full awakenings.

01

Before sleep

Raizz Band starts by learning your baseline patterns as you wind down and fall asleep. The Raizz app guides a simple pre-bed sleep ritual, and you choose a vibration intensity that feels comfortable. That same intensity setting is the one the band uses later during the night. The goal of this phase is to support falling asleep faster, without adding complicated steps.

02

During sleep

During sleep, this band continuously senses your state on the wrist and looks for emerging disruption patterns. A very gentle vibration is triggered a few minutes before a predicted micro-awakening. The body senses the vibration and interprets it as safe to stay asleep, which can reduce the chance that the micro-awakening happens. This response is automatic, and it is personalized to your sleep pattern and varies by sleep stage.

03

Next morning

In the morning, Raizz turns the night into guidance you can actually use that day. The app helps you connect what happened overnight with your routine and choices, grounded in established behavioral sleep science. The closed-loop system also learns from outcomes, so each sense and respond cycle informs the next one. Over time, it aims to feel less like a gadget and more like a steady nightly habit.

Research

Peer-reviewed studies on the closed-loop vibration technique Raizz uses.

Peer-reviewed papers have studied the same closed-loop vibration technique Raizz uses, across nap and full-night settings. The cards in this section summarize those findings and cite the original journals.

A 2024 study found that weak, heart-rate-matched vibration reduced wake-after-sleep-onset by roughly 24% and improved subjective sleep quality scores in people with poor sleep.

Kwon et al. (2024), Frontiers in Neuroscience

A 2021 study found that closed-loop vibration deepened slow-wave sleep and significantly improved next-day declarative memory retention.

Choi et al. (2021), Sleep

A 2019 study found that vibration only works when tuned very close to a person's real heart rate, which is the technical premise the other two studies build on.

Choi et al. (2019), Sensors

Findings from independent, peer-reviewed studies of closed-loop vibration stimulation, not a Raizz-run clinical trial.

Capabilities

How does this sleep bracelet sense, decide, and respond on your wrist?

Raizz is built for people who want a wearable that does more than summarize the night. Each capability below is designed to keep the experience calm, automatic, and wearable every night.

Raizz Band on a wrist under a blanket, bedroom lights dim
Closed loop

Responds before you wake

Raizz uses a closed-loop process: it senses your sleep state, decides locally on the wrist, acts with a gentle vibration, then learns from what happened next. The vibration is timed to arrive a few minutes before a predicted micro-awakening. The goal is to lower the chance that a small arousal becomes a full awakening. This is the key difference between passive tracking and active night-time response.

  • Detects sleep stages
  • Predicts micro-awakenings
  • Vibrates automatically
  • Adapts after responses
Hand holding a phone with sleep app settings open
Personal fit

Tuned to your pattern

Raizz personalizes vibration around your sleep pattern rather than using a single generic schedule. Vibration differs by sleep stage, because your body responds differently across the night. You set the intensity during your pre-bed ritual, and that same setting is used during sleep so the experience stays consistent. The system’s decisions are driven by your state in the moment, not by manual taps at night.

  • Stage-specific vibration
  • Pattern-based timing
  • One intensity setting
  • No night interaction
Person sitting at breakfast reviewing last night’s sleep notes
Daily guidance

Turns data into action

A wrist device is only useful if it helps you do something different tomorrow. Raizz combines what it sensed overnight with simple prompts and guidance grounded in established behavioral sleep science. The app is designed to translate the night into clear next steps, without overwhelming you with charts. This is meant to reduce the common experience of tracker fatigue, where scores increase but mornings still feel flat.

  • Clear morning recap
  • Simple behavior prompts
  • Less score chasing
  • Built for consistency

Comparison

How does Raizz compare to other sleep bracelet options and sleep tools?

This table compares what Raizz does versus common devices to help sleep, using straightforward feature checks.

RaizzSleeping PillsSleep MasksWhite Noise DevicesTracker Wearables
Tracks sleep stages and disruptions✓———✓
Personalizes based on your patterns✓———✓
Responds automatically while you sleep✓————
Drug-free approach✓—✓✓✓
One-time purchase category✓—✓✓✓
Works with a simple nightly routine✓✓✓✓✓

Outcomes

A band that stays focused on the moment you need help.

Raizz is built for nights where the hard part is not knowing your score, it is staying settled. These benefits describe what the band is designed to do in real use.

1

Less broken sleep

Raizz is designed to catch emerging arousal before it becomes a full awakening. It responds with a gentle vibration timed ahead of predicted micro-awakenings. The goal is to help you stay asleep longer in the parts of the night where you usually pop awake. The experience is meant to stay quiet and automatic, not interactive.

2

Faster settling

Many nights start with a long ramp down, even when you are tired. Raizz supports falling asleep faster by pairing a pre-bed ritual with night-time closed-loop response. The device still records your stages, but the product goal is not only reporting. The aim is a shorter path from lights out to sleep.

3

More usable mornings

Raizz is built to help you understand what changed, without turning sleep into a homework assignment. The app summarizes the night and gives guidance grounded in established behavioral sleep science. The intent is to reduce the loop of chasing scores and still feeling tired. A calmer morning summary can make it easier to stay consistent.

4

Wear it nightly

A wristband only helps if it is comfortable enough to keep wearing. Raizz is designed around a simple pattern: set intensity before bed, wear through the night, review in the morning. There is no need to wake up and trigger anything manually. Consistency is a core product requirement, not an afterthought.

Built for

Raizz fits three common nights that tracking alone does not fix.

Each scenario below maps to a specific way the Raizz Band senses and responds during the night.

1

Long time to fall asleep

If your mind and body take a long time to settle, a sleep bracelet that only reports the delay can feel frustrating. Raizz pairs a pre-bed ritual with the same vibration intensity used later in the night. The goal is to support falling asleep faster, then keep that calmer state from breaking. This keeps the focus on what you feel in the morning, not only what you see in an app.

2

Waking up repeatedly

If you wake up several times, the problem is often the moments right before each awakening. Raizz looks for disruption patterns and triggers a gentle vibration a few minutes before a predicted micro-awakening. The intent is to reduce how often those small arousals turn into full wake-ups. This is where a band that acts in real time can matter most.

3

Tired after tracking

If you already use a sleep tracker and still wake up tired, more graphs might not help. Raizz is designed to keep the tracking, then add automatic response during sleep. The app also turns the night into guidance grounded in established behavioral sleep science. The goal is to help you move from observation to improvement without adding complexity.

Who Built This

Backed by real expertise, stated plainly

Holly He
Founder & CEO

12+ years in product design at Apple, contributing to Vision Pro, Apple Health, and iPhone. MS from Stanford.

Edward Carryer
Advisor

Adjunct Professor Emeritus, Stanford Mechanical Engineering; former Director of the Smart Product Design Lab.

Dr. Joshua Lo, MD
Advisor

Sleep Medicine Fellow at Stanford; oversees clinical protocol design and medical validity.

In the box

Raizz includes the Band, app, and charging base.

Raizz Band works with the Raizz app for your pre-bed ritual, overnight closed-loop vibration, and morning guidance, plus a charging base for daily use.

●

Raizz Band

The wearable band worn overnight.

●

Raizz App

Sleep tracking, journal, and vibration history.

●

Charging Base

Docks the band between nights.

FAQ

Questions people ask before choosing a sleep tracker bracelet.

Each answer is written to stand alone, with the specific mechanism Raizz uses and the evidence sources clearly separated.

What does this sleep bracelet track during the night?
Raizz tracks when you fall asleep and estimates different sleep stages through the night. Raizz also detects disruption patterns such as restless moments and emerging arousal. This sleep bracelet uses this real-time sensing to decide when to respond, not only to summarize the night later. Tracking is part of the system, because the response depends on what the wrist detects in the moment. As a sleep tracking bracelet it estimates stages through the night, so the morning view reflects what actually happened.
How is Raizz different from a normal sleep tracker bracelet?
A typical sleep tracker bracelet records sleep data and shows charts after you wake up. Raizz also responds during sleep, using gentle vibration timed before a predicted micro-awakening. The response is automatic, based on your current sleep state, and it feeds back into the next decision. This is why Raizz is positioned as a sleep bracelet that can actively improve sleep quality, not only report it.
What does closed-loop mean on a sleep bracelet?
Closed-loop means the system continuously senses, decides, acts, and then learns from the outcome. Raizz senses your sleep state on the wrist, decides locally when to intervene, and triggers a gentle vibration at the right time. After the response, the system uses what happened next to adapt the next decision. Closed-loop matters because the timing is personalized to your sleep pattern rather than fixed on a preset schedule.
When does the vibration happen, and is it automatic?
Raizz vibration is designed to happen during sleep a few minutes before a predicted micro-awakening. Raizz triggers that vibration automatically based on your current sleep state, not because you press a button at night. The intensity you choose during your pre-bed sleep ritual is the intensity used during sleep as well. The goal is to support staying asleep without asking you to manage the device mid-night.
Will a sleep wristband vibration wake me up?
Raizz is designed around very gentle vibration intended to reduce micro-awakenings, not cause them. The vibration is timed ahead of a predicted micro-awakening, when the body is starting to shift toward waking. The intent is for the body to interpret the sensation as safe to stay asleep, lowering the chance of a full awakening. You control intensity before bed, which helps you keep the experience within a comfortable range. Worn as a sleep aid wristband, the vibration stays gentle enough to settle you rather than rouse you.
Can I control the vibration intensity on this smart sleep band?
Yes, you set the vibration intensity during your pre-bed sleep ritual in the Raizz app. That same intensity setting is applied during the night, so you do not need to make choices while you are trying to sleep. During sleep, the timing of vibration is automatic and based on your sleep state. This keeps control simple while still allowing personalization to your comfort.
How does Raizz personalize the vibration?
Raizz personalizes vibration timing to your sleep pattern and varies vibration by sleep stage. The band detects when you fall asleep and tracks stages through the night, then uses those signals to decide when to intervene. The closed-loop design means each response informs the next decision, so the system adapts over time. This personalization is meant to fit your night rather than forcing your night to fit the device.
What results has Raizz reported for this sleep bracelet?
Raizz reports three headline outcomes: 25% less time to fall asleep, 30% higher overall self-rated sleep quality, and 2x stronger biological indicators of deep sleep. The self-rated measure is explicitly self-rated, meaning it reflects how people say they slept. The deep-sleep measure is described as biological indicators, meaning objective signals. These are Raizz’s published results, separate from peer-reviewed studies on the vibration technique.
What peer-reviewed research exists on the vibration technique Raizz uses?
Three peer-reviewed studies by the same research group examined closed-loop, heart-rate-matched vibration across nap and full-night settings, published from 2019 to 2024. A 2024 study in Frontiers in Neuroscience found reduced wake-after-sleep-onset and improved subjective sleep quality in people with poor sleep quality. A 2021 study in Sleep found deeper slow-wave sleep and improved next-day declarative memory retention in healthy adults. A 2019 Sensors study showed the vibration needed very close heart-rate tuning to work.
What comes with Raizz, and what do I set up first?
Raizz includes the Raizz Band, the Raizz app, and a charging base. The first step is to set up the app and choose a comfortable vibration intensity during your pre-bed sleep ritual. After that, the band can detect sleep stages and run closed-loop vibration automatically during the night. In the morning, the app provides a recap and guidance based on what the band sensed.
Instagram Facebook X (Twitter) YouTube

Have questions, want to join us, or simply want to connect? We’d love to hear from you — feel free to reach out at

[email protected]

Privacy Policy Terms of Service

© 2026 AxiLab. All rights reserved