Someone posted CT scans of popular health wearables today and I've been staring at them for an hour.
Here's what struck me: the inside of a $400 smart ring looks almost identical to the inside of a $150 one. Same basic sensor array. Same tiny battery. Same flex PCB curved around the inner wall. The expensive one has maybe 2-3 extra components.
I've been wearing an Oura Ring for two years. I check my sleep scores religiously. I track my HRV like it means something. And now I'm looking at a CT scan showing me that the hardware doing all this is... a couple of LEDs, a photodiode, an accelerometer, and a temperature sensor. That's it.
The real product isn't the hardware
This isn't a complaint. It's an observation about where value lives in 2026.
The bill of materials for most health wearables sits somewhere between $15 and $40. The rest is software, algorithms, and brand. Oura's sleep staging algorithm is what you're paying for. The titanium shell is nice, sure. But the intelligence is in how they process the PPG signal from that tiny green LED bouncing light off your blood vessels.
Apple Watch? Same story at a different scale. The Series 10 has roughly $65 in components. You're paying $399 for watchOS, the health algorithms, the ecosystem lock-in, and that satisfying tap on your wrist.
What the CT scans actually reveal
The most interesting thing in these scans isn't what's there. It's the empty space.
Most wearables are 40-60% air by volume. There's a cluster of components near the sensor window, a battery taking up maybe a third of the space, and then... nothing. Just structural material and void.
This tells me two things. First, miniaturization in consumer health tech hasn't hit its floor yet. There's physical room for more sensors, bigger batteries, or smaller form factors. Second, the current generation of wearables is constrained by battery chemistry, not by PCB design. They could pack more in. They just can't power it.
The subscription play makes more sense now
I used to be annoyed that Oura charges $6/month for their subscription on top of the hardware cost. Looking at these CT scans, I get it now. The hardware is a commodity. Two LEDs and a photodiode cost pennies. The value is in the interpretation layer.
Whoop figured this out early. They literally give you the hardware for free and charge $30/month. The strap is worth maybe $20 in parts. The algorithms and coaching are the product.
What this means for hardware startups
If you're building a health wearable in 2026, the CT scans make your competitive position pretty clear. You can't win on hardware differentiation. Everyone has access to the same MEMS accelerometers, the same optical heart rate sensor designs, the same Nordic nRF chips.
You win on three things: sensor fusion algorithms, data interpretation, and what you do with the insights. The company that turns raw PPG data into an accurate glucose estimate without a needle wins the next decade. Not because of better hardware. Because of better math.
I find this weirdly encouraging. It means the barrier to building health hardware is lower than ever. A two-person team could design a competitive wearable sensor package today. The hard part, the part that actually matters, is what you do with the data after you collect it.
The CT scans don't lie. There's nothing magic in the box. The magic is in the code.