A woman’s sleep study came back with good news: her sleep had measurably improved. She didn’t believe it, because every morning her Fitbit told her she’d slept badly, and she had started staying in bed longer to make the number go up. Her case is one of several in a paper that gave this behavior a name, and sleep clinics now see it walk through the door regularly: patients arriving with a graph, convinced they have a disorder that testing says they do not have. The devices behind those little graphs are a market expected to reach $58 billion by 2030, and most of them measure from the wrist or finger a process that happens in the brain. When a 2026 study put three of the most popular wearables up against a laboratory sleep test, the gap between what the devices reported and what actually happened ran to more than an hour on some measures. A consultant in sleep medicine at one of London’s biggest hospitals has a two-word description for the score on your app, and the researchers who named the condition it produces say the fix is not a better tracker. It starts with what the number is actually counting. Getty Images / unsplash Sleep isn’t just something we do because we’re tired (if only it were that simple). As sleep researcher Robert Stickgold writes in Scientific American, researchers have learned that sleep appears to be needed for the optimal functioning of a “multitude of biological processes,” from the immune system and hormonal balance to emotional health, learning and memory, and the clearance of toxins from the brain. And yet, for all that we’ve learned, exactly what we get from spending a third of our lives unconscious has “long mystified scientists.” So perhaps it’s no surprise that many of us are curious about what happens during our own visits to the land of Nod. “Sleep trackers,” as Dr. David Backwell, a medical doctor working in sleep medicine, recently wrote for Daily Maverick, “allow you to pull back this veil and see what is going on when your eyes are closed.” The technology itself isn’t exactly new. According to Ashitha Nagesh, writing for the BBC, the first commercial fitness tracker to incorporate sleep analysis was the Fitbit Classic in 2009. In the time since, sleep tracking has become increasingly widespread, making its way into wrist-worn devices from companies like Garmin, Whoop and Apple, as well as smart rings such as Oura, Ultrahuman and RingConn. And these devices are no longer used mainly by athletes and wellness advocates, either. As Bridget Chapman, deputy editor of Forbes Vetted, writes, “People across the spectrum are monitoring their sleep stats with health wearables, from tired Midwestern moms to overworked C-suite executives.” And the market certainly reflects that interest. Chapman writes that the sleep-tech market is expected to be worth $58.21 billion by 2030. That’s more than double its 2023 market size, with an expected annual growth rate of 11.7%. You don't even necessarily need a dedicated wearable to get in on it. Many smartphones and smartwatches now incorporate sleep monitoring directly into their health apps. Diana Light / unsplash Alongside the rise of sleep tech, the way we think about sleep has changed, too. Looking back at the early days of wearables, when sleep tracking was just a “secondary detail,” Chapman writes that “hustle culture” was gaining traction, with declarations such as “I’ll sleep when I’m dead” and the “rise and grind” lifestyle making sleep less valued. But she says that conversation has since changed. “The conversation surrounding sleep was changing for many reasons, but two most notably: Hustle culture in the workplace was greeted by burnout, and COVID-19 kept millions inside their homes.” As priorities shifted, so did the emphasis on getting better rest and creating a more comfortable bedroom environment. And perhaps that helps explain how we got here. Chapman describes today’s world as “REM-obsessed,” and it certainly seems that way: Sleep has become yet another aspect of our lives to “maxx.” The term sleepmaxxing has emerged to describe the increasingly elaborate ways people are trying to improve their nights. As neurologist Aatif Husain, MD, told HealthCentral, “Sleepmaxxing is a social media-driven, wearables-enabled trend that focuses on optimizing sleep quantity and quality via lifestyle habits, devices, diet and supplements.” And this is where sleepmaxxing and sleep tracking start to overlap. Once we’re treating sleep as something we can optimize, it becomes tempting to measure our progress, too. But how much can those numbers and graphs actually tell us? Shane / unsplash Before you go getting too attached to the graphs and numbers, it helps to understand what a wearable sleep tracker is actually measuring. If you’ve ever seen someone undergo a sleep study, you might’ve noticed that there are significantly more wires involved than someone simply wearing an Apple Watch to bed. That’s because polysomnography (PSG), widely regarded as the “gold standard” for evaluating sleep continuity and architecture, records things like brain activity, eye movements, muscle tone and heart rate. Your wearable simply doesn’t have all that information to work with. As sleep scientist Dean J. Miller puts it, “Surfing is done in the ocean, planes fly in the sky, and sleep occurs in the brain. So how can we measure sleep from the wrist or finger?” Well, it depends on the device. In general, sleep trackers give you a report of your night, showing things such as time awake, light sleep, deep sleep and REM sleep, and many also assign an overall sleep score. Many use actigraphy, which relies on movement data collected through sensors such as accelerometers, alongside photoplethysmography (PPG), which uses light to detect changes in blood flow. “Actigraphy assumes a person is awake when they’re moving and asleep when still. Simple,” Miller explains. PPG can provide information such as heart rate and breathing rate, while more complex devices may incorporate additional signals such as heart-rate variability, blood oxygen levels and temperature. These different signals can then be processed by algorithms to estimate sleep patterns, disturbances and stages, with “estimate” being the operative word here. Andrej Lišakov / unsplash Consumer sleep trackers have become increasingly reliable at estimating how long you sleep, but they’re still less reliable when it comes to determining which stage of sleep you’re in. As Backwell explains, reviews have found that consumer trackers are “inconsistent in their sleep staging accuracy.” They can perform similarly to clinical actigraphy, he says, but aren’t diagnostic. A 2026 study published in Sleep Medicine illustrates the point. It compared the Apple Watch Series 7, Fitbit Charge 5 and Polar Vantage M2 with polysomnography (PSG) and actigraphy. The researchers found “parameter-specific bias and limited agreement” with the comparison methods. Compared with PSG, the Fitbit estimated 57.7 more minutes of light sleep, on average, while the Apple Watch estimated 73.8 fewer minutes of light sleep and 30.3 more minutes of REM sleep. As such, the researchers concluded that the devices may be more appropriate for “longitudinal self-monitoring rather than clinical-grade assessment of sleep architecture.” In other words, your wearable can give you useful clues about your sleep, but you probably shouldn’t treat every minute of “deep” or “REM” sleep on your app as gospel. And apparently, the same goes for your sleep score: The concept of a sleep score is “completely made up,” Dr. Alana Hare, consultant in sleep medicine at the Royal Brompton Hospital in London, told the BBC. "There's nothing recognized in sleep science that is a 'sleep score,'" she said. “That’s just been created by manufacturers.” DreamWorks Pictures The measurements might not be perfect, but that doesn’t mean the data is useless. In fact, Miller argues that “this level of detail isn’t essential for improving the basics of your sleep.” Your wearable may not be able to tell you with clinical precision that you got exactly 82 minutes of REM sleep, but it might help you notice “what is really going against what you assume is happening,” Backwell explains. Maybe you’re regularly going to bed later than you thought, waking more often than you realized, or sleeping less on certain nights. A tracker might reveal, for example, that your bedtime regularly drifts later on weekends or that certain habits coincide with more fragmented sleep. "Noticing these patterns is the first step toward changing some behaviors for the better," Backwell explains. Dr. Angela Holliday-Bell, a board-certified physician and certified sleep specialist, takes a similar view, saying sleep trackers can be "a tool to support behavioral change." She explains that they can “highlight patterns you may not notice on your own, like inconsistent bedtimes or too much time spent awake,” according to Forbes Vetted. But sleep expert Carleara Weiss offers an important caveat: “Keep in mind that they are not medical devices,” she says. Rather than using the data to make self-treatment decisions, she recommends using it “as an awareness tool combined with how you feel about your sleep.” And that’s probably the best way to think about consumer sleep tracking: not as a replacement for formal testing or a nightly performance review, but as a tool for noticing patterns in your sleep habits. Especially because the former, it seems, has a funny way of keeping us up at night. bruce mars A 2017 paper introduced the term orthosomnia, combining “ortho,” meaning correct or straight, with “insomnia.” It describes people who become preoccupied with “improving or perfecting their wearable sleep data,” in what the authors called “a perfectionist quest for the ideal sleep.” The paper included several clinical cases illustrating how wearable data could become a source of concern. One patient became convinced that his daytime fatigue and cognitive difficulties were connected to not getting enough sleep according to his tracker. Another, despite improvements seen in an actual sleep study, was still worried because her Fitbit told her she was sleeping poorly. In some of the cases described, people even spent longer in bed in an effort to improve their tracker data, illustrating just how far the focus on the numbers could go. The paper is only a small case series, and orthosomnia is not a recognized medical disorder with established diagnostic criteria. Instead, it’s a proposed term for a phenomenon that researchers are still trying to understand. But the underlying concern is still being seen in clinical practice. Doctors have told the BBC that they’ve noticed signs of it in their patients, with some arriving with tracker data, convinced they have a sleep disorder when medical testing suggests otherwise. And they warn that this fixation “is actually making people’s sleep worse.” Dr. Neil Stanley, a sleep expert, argues that “gamifying sleep” is creating more disordered sleeping. “The thing with tracking your sleep is that it gives you a number, and this means you have a target,” he told the BBC. “So you get into this cycle of worrying about your quality of sleep or the quantity of sleep based on figures.” And that’s where things can start to become counterproductive. As Arianna Huffington, who uses an Oura Ring herself, told Forbes Vetted, “the tracking data is a means to an end—the goal is more and better sleep, not more sleep data.” In other words, there’s a difference between wanting to sleep better and turning sleep into another performance metric. “You shouldn’t be aiming for a score when you wake up,” Husain told HealthCentral. Getty Images “The pressure to get perfect sleep is embedded in the sleepmaxxing culture,” Eric Zhou, PhD, writes for Harvard Health. But even so—and TikTok influencer connotations aside—the idea behind it isn’t inherently bad. Its aim, as Dr. Anita Shelgikar told CNN Health, is to “optimize sleep quality and quantity.” And although Zhou notes that sleepmaxxing hasn’t been studied as a “package” per se, Kristen Rogers, writing for CNN Health, explains that “Many of the practices included in sleepmaxxing focus on basic habits that experts have long touted as the holy grail for sleep health.” These include sleeping in a cool, dark and quiet room; limiting exposure to light from screens and other sources before bed; avoiding alcohol and caffeine; and going to bed at a regular time. In this sense, as Husain told HealthCentral, sleepmaxxing is “a rebrand of sleep hygiene but on steroids.” But the trend also mixes those sensible, tried-and-true basics with other “hacks” that Rogers notes “may be questionable at best and harmful at worst.” Interestingly, sleep tracking, along with weighted blankets, red light exposure, supplements and kiwis (yes, you read that right), is listed among the recommendations that “may or may not work.” Supplements are another common part of sleepmaxxing, particularly melatonin and magnesium. But experts told CNN that they’re not necessary for most people, and regularly relying on them to address difficulty falling asleep could mask an underlying sleep disorder that needs professional assessment. Shelgikar also cautions that magnesium supplements can worsen some medical conditions. Husain similarly points out that melatonin supplements can interact with other medications and may contain much more of the hormone than the body naturally produces. And then there are hacks that experts actively warn against, like mouth taping. Rogers reports that experts have criticized the TikTok trend as potentially dangerous, particularly for people with obstructive sleep apnea, and note that it can also cause soft-tissue damage. But whether it's taping your mouth shut, popping in nasal dilators, or eating two kiwis before bed, all these efforts to improve our nights raise a bigger question. Curated Lifestyle / unsplash As Zhou writes for Harvard Health, “While prioritizing restful sleep is commendable, setting perfection as your goal is problematic.” Even good sleepers have less-than-ideal nights a couple of times a week. In other words, a bad night here and there is normal, so expecting every night to be perfect is probably setting yourself up for disappointment. As Hare puts it, “It’s great that there’s more focus on sleep as part of wellness. But sleep just does not respond well to attempts to perfect it.” And perhaps that’s the most reassuring thing about all of this. You don’t need a smart ring, a $300 sleep gadget, a supplement cabinet and a 17-step bedtime routine to give yourself a better chance of sleeping well. Some of the most consistently recommended strategies are remarkably unglamorous: things like a regular sleep schedule, enough daylight and exercise, and a little time to wind down before bed. Hare says it’s all about keeping it simple: “anything else, you don’t need it.” But of course “No two snoozers are the same,” as Janet Lee writes for HealthCentral. And if your wind-down routine involves something a little more elaborate, well, go wild. As Shelgikar told CNN, “Different people will find different wind-down approaches to be beneficial. The key is having a consistent routine and consistent sleep-wake schedule, as these approaches can help with obtaining restful sleep.” The important thing is not to let that routine “turn what should be a restorative process into a high-pressure chore.” For some people, she says, being overly attentive to sleep optimization and sleep patterns every night can increase stress and worsen sleep over time. And that’s an important distinction when it comes to sleep tracking, too. If looking at your data helps you notice useful patterns without making you anxious about every number, it can be a useful tool. But if tracking leaves you worried or lying awake wondering whether you’re getting enough deep sleep, there’s a pretty good chance you’ve already lost sight of the goal. As Backwell puts it, the trick is to “hold the data lightly, not worry about the results and know its limitations.” Because while we can measure certain things about sleep, we can’t micromanage our way into a perfect night. At the end of the day, as Backwell writes, "Sleep remains outside of voluntary control." So maybe the best sleep hack of all is knowing when to stop optimizing and just get some rest.
