Accuracy & Validation Master · As of July 2026

Accuracy you can trust,
at every layer.

Luna is a full-stack health system, and accuracy is engineered into every layer of it. This page doesn't just walk you through core biomarker testing, it walks you through how accuracy decisions taken at hardware, biomarker measurement, analysis, environmental conditions, and real-world scenarios are measured in Luna.

98.4

HR accuracy %

95.4

HRV accuracy %

97.2

Steps agreement %

365,676

Readings benchmarked

We don't grade ourselves against other wearables

We measure against instruments that set the standard.

It is tempting to say we are more accurate than this ring or that watch. We won't. Comparing to another consumer device assumes that device is right, and too often it isn't. Most public wearable accuracy data is marketing data. If we want to lead where health guidance goes next, our job is to raise the bar, not match it.

Heart ratePolar chest strap. Chest placement gives the highest signal quality and is the best consumer-grade reference to optimize toward.

HRVPolar H10, the accepted chest-strap standard used in sports-science labs.

StepsLiteral manual step counting, plus Apple Watch head-to-head, removing device-to-device bias.

RespiratoryInternal lab tests against industrial-grade equipment (CPAP-class references).

Consumer-device comparisons appear only as context, never as ground truth.

Accuracy is not one test. It is engineered at five layers.

Explore the stack

01Sensors 02LifeOS Edge 03Environment 04LifeOS Cloud 05Certifications

It starts with the signal

Better guidance begins with better raw data. Luna senses every second through multiple light channels and a six-axis motion sensor, so the signal we build on is among the richest any wearable captures. Nothing downstream can be more accurate than the signal it starts from.

Component	Specification
Optical sensor	7-LED optical array (4 green + 1 multi-wavelength green/red/IR) with 4 high-sensitivity photodiodes for stronger signal across HR, SpO2, HRV, and stress.
Motion	6-axis high-precision IMU (3-axis accelerometer + 3-axis gyroscope) for activity, workout recognition, and sleep analysis.
Processor	Ultra-low-power wearable processor (Apollo3 Blue Plus) tuned for continuous per-second sensing and extended battery life.
Skin temperature	High-accuracy skin temperature sensor for continuous wellness tracking and recovery insight.
Wear detection	SAR + PPG combined wear detection for reliable on-body sensing.
Water resistance	5ATM rated for continuous sensing in and around water.
Battery	160 mAh, managed by a dedicated charger IC for efficient, safe charging.
Feedback	Vibration motor and RGB indicator for haptics and device status.

Then we make it true for you

Your body is not the average body. LifeOS Edge, our on-device firmware, turns raw signal into accurate data across the variables that trip up other wearables. It is validated in controlled conditions, then with real people, and gets better with every firmware release.

Where we stand

We are proud of these results, and we are not claiming perfection. No sensor is right for every body in every moment. What we commit to is this: we keep finding the edge cases, and we keep closing them, release after release. Accuracy at Luna is a direction of travel, not a finish line.

Validated across	Why it matters for accuracy
Skin tone	Optical absorption varies with melanin; Edge normalizes so readings hold across all skin tones.
Body hair	Hair scatters light between sensor and skin; compensated so signal quality stays high.
Band placement	Sensor-to-skin position shifts the optical path; corrected across realistic wear positions.
Band tightness	Loose or tight fit changes contact pressure and perfusion; handled across a fit range.
Workout intensity	Motion artifact is where optical HR usually fails; the 6-axis IMU separates it from true signal.
Sweat & moisture	Moisture alters reflectance; validated wet and dry so readings stay stable mid-workout.
Age & gender	Physiological baselines differ; models validated across demographic groups, not one cohort.
Hand movement	Everyday motion adds noise; filtered so resting and active readings both stay clean.

Firmware release log · LifeOS Edge 1.3.1 · full per-release notes pending internal export

We take it everywhere you go

Deserts, humidity, altitude, snow, a hard knock, and five atmospheres underwater. We test the signal in each, because your life doesn't happen in a lab and your data shouldn't only hold up in one. Every one of the 19 reliability and durability tests passed, with zero failures.

#	Test	What it proves	Result
01	Drop Test	Survives real-world drops without functional or optical failure	PASS · 6 SAMPLES
02	Rolling Test	Endures repeated tumbling and rough handling	PASS · 6 SAMPLES
03	5ATM Water Resistance	Sensing holds under 50 m equivalent water pressure	PASS · 4 SAMPLES
04	Dust Resistance	Sealed against fine particulate ingress	PASS · 4 SAMPLES
05	High Temperature	Operates in desert-grade heat	PASS · 5 SAMPLES
06	High Temp + Humidity	Holds up in hot, humid climates	PASS · 5 SAMPLES
07	Low Temp Storage	No damage after cold storage	PASS · 4 SAMPLES
08	Low Temp Operating	Functions in freezing conditions	PASS · 4 SAMPLES
09	Temperature Shock	Withstands rapid hot-to-cold swings	PASS · 4 SAMPLES
10	Salt Spray	Resists corrosion from coastal and sweat salt	PASS · 4 SAMPLES
11	Artificial Sweat (Acidic)	Finish and sensor resist acidic sweat	PASS · 3 SAMPLES
12	Artificial Sweat (Alkaline)	Finish and sensor resist alkaline sweat	PASS · 3 SAMPLES
13	Alcohol Abrasion	Survives repeated cleaning and wipe-downs	PASS · 5 SAMPLES
14	Adhesion Test	Coatings and bonds stay intact	PASS · 5 SAMPLES
15	Pencil Hardness	Surface resists scratching	PASS · 5 SAMPLES
16	Cross-Cut Test	Coating adhesion holds under cut-grid stress	PASS · 4 SAMPLES
17	Cosmetic Resistance	Appearance survives everyday cosmetics	PASS · 6 SAMPLES
18	Stain Resistance	Resists staining from common substances	PASS · 4 SAMPLES
19	Vibration Abrasion	Endures sustained vibration wear	PASS · 4 SAMPLES
	Overall conclusion	Every reliability and durability test passed	19 / 19 PASS

And we keep learning, in real time

Clinical research is a starting point, but it can't see how a stressful day changes the way magnesium works for you. Because Luna senses continuously and models your biology as it goes, LifeOS Cloud discovers how your habits move your own biomarkers, and turns that into guidance built for you, not for a population.

Go deeperThe full story of what LifeOS Cloud discovers lives in the LifeOS Research space: how habits move real biomarkers, tracked over 1.5 years of building.

See LifeOS Research →

Capability	What it does
Per-second sensing	Continuous capture creates the density of data needed to model an individual, not an average.
Personalized health model	A live per-user model (PHM) updated in a real-time feedback loop from that user's own signal.
Habit-to-biomarker discovery	Anonymized data reveals how specific habits move a person's biomarkers over time.
Research foundation	Built over 1.5 years of research; guidance is grounded in real discovery, not fixed rules.

Research stats · LifeOS Cloud · headline discovery numbers pending from research space

Held to a responsible standard

Accuracy without responsibility is not accuracy at all. Everything Luna ships is held to the same standard as the data it produces: low-emission wireless that stays within strict radio limits, battery safety validated against thermal and charge-fault conditions, and restrictions on hazardous materials so the device is safe on your skin and safe at end of life. Twelve certifications are held today across the EU, UK, USA, UAE, Japan, and Australia and New Zealand, spanning radio conformity, electrical safety, EMC, hazardous-substance limits, and e-waste take-back. Each one is an independent check by a regulator, not a claim we make about ourselves, and the list grows with every new market Luna enters.

CE REDEuropean Union

RoHSEuropean Union

WEEEEuropean Union

UKCAUnited Kingdom

CA65USA

UAE TDRAUnited Arab Emirates

UAE RoHSUnited Arab Emirates

Japan MICJapan

RCMAustralia / NZ

FCCUSA

WERCJapan

German WEEEGermany

Certification	Region	What it covers
CE RED	European Union	EU Radio Equipment Directive: radio, safety, and EMC conformity for wireless devices sold in the EU.
RoHS	European Union	Restriction of Hazardous Substances: limits lead, mercury, cadmium and other hazardous materials.
WEEE	European Union	Responsible end-of-life collection and recycling compliance for electronics.
UKCA	United Kingdom	UK Conformity Assessed: the mark for products placed on the Great Britain market.
CA65	USA · California	Proposition 65: warning and limits on exposure to listed chemicals in California.
UAE TDRA	United Arab Emirates	Telecommunications regulatory approval for wireless devices in the UAE.
UAE RoHS	United Arab Emirates	UAE restriction of hazardous substances, aligned to EU RoHS.
Japan MIC	Japan	Ministry of Internal Affairs radio certification (Giteki) for Japan.
RCM	Australia / NZ	Regulatory Compliance Mark: electrical safety and EMC/radio compliance.
FCC	USA	Federal Communications Commission authorization for radio-frequency emissions.
WERC	Japan	Registration for compliant electronics recycling in the Japanese market.
German WEEE	Germany	German national WEEE (ElektroG / stiftung ear) e-waste take-back registration.

Heart rate · vs Polar chest strap and 4 reference devices

98.4

Mean accuracy %

259,995

Paired readings benchmarked

2.1

Mean absolute error, bpm

0.97

Mean Pearson correlation

Weekly trend · 225 sessions · May 04 – Jul 14 2026

Weekly heart-rate accuracy trend, May to July 2026

MAE improved from 2.25 bpm (week of May 04) to 1.73 bpm (week of Jul 13). A MAE under 5 bpm is generally considered a good reference point.

By reference device

Reference	Accuracy %	MAE bpm	Pearson r	Paired readings
Polar (standard)	98.48	2.04	0.97	209,352
Apple Watch	98.72	1.80	0.97	9,342
Zepp	98.53	2.12	0.97	16,225
WHOOP	97.40	3.61	0.96	2,505
Garmin	97.98	2.79	0.94	22,571

Polar chest strap carries the most weight by design: it is the reference standard. 259,995 paired comparisons in total.

Session accuracy distribution

Lowest single session: 95.9%. 168 of 225 sessions above 98%.

HRV · vs Polar H10 · the hardest metric to get right

95.4%

Agreement with the Polar H10 chest-strap standard across overnight and resting benchmarks. HRV is measured in milliseconds between beats.

4.6%

Mean absolute percentage error across sessions

+1.87 ms

Directional bias: under 2 ms, well inside noise for HRV

Luna vs reference · anonymized benchmark sessions · 27 to 117 ms range

HRV agreement scatter plot, Luna vs Polar H10 reference

Points on the line are perfect agreement. Accuracy holds across low and high HRV, where errors usually appear.

Sleep · vs Apple Watch and WHOOP

4

User types tested

72

Nights compared

17.3

Mean delta vs Apple, min

12.7

Mean delta vs WHOOP, min

Total sleep · Luna vs Apple Watch · 40 nights

Total sleep per night, Luna vs Apple Watch

Mean absolute delta 17.3 min per night.

Total sleep · Luna vs WHOOP · 32 nights

Mean absolute delta 12.7 min per night.

User types tested

#	Sex	Age
01	Male	30
02	Female	36
03	Male	46
04	Female	29

Steps · literal manual counting + Apple Watch

97.2

Median agreement % · 308,371 steps recorded

Manual counting removes device-to-device bias entirely, and Apple Watch head-to-head sessions add real-world coverage. Median agreement is 97.2%, with best sessions above 99%.

Reference · Manual count Reference · Apple Watch

Head-to-head sessions

Reference	Luna	Reference	Diff	Accuracy %
Apple Watch	1,805	1,700	+105	93.8%
Apple Watch	1,817	1,851	-34	98.2%
Manual count	761	876	-115	86.9%
Apple Watch	2,024	1,985	+39	98.0%
Manual count	1,970	1,945	+25	98.7%
Apple Watch	2,621	2,628	-7	99.7%
Manual count	1,991	1,921	+70	96.4%
Apple Watch	1,876	1,862	+14	99.2%

Representative sessions shown, not cherry-picked. Median across the program: 97.2%.

Luna vs reference steps · per session

Steps count, Luna vs reference device by session

Bars near equal height mean close agreement. Manual and Apple Watch references combined.

Certifications

Held to a responsible standard

Accuracy without responsibility is not accuracy at all. Everything Luna ships is held to the same standard as the data it produces: low-emission wireless that stays within strict radio limits, battery safety validated against thermal and charge-fault conditions, and restrictions on hazardous materials so the device is safe on your skin and safe at end of life. Twelve certifications are held today across the EU, UK, USA, UAE, Japan, and Australia and New Zealand, spanning radio conformity, electrical safety, EMC, hazardous-substance limits, and e-waste take-back. Each one is an independent check by a regulator, not a claim we make about ourselves, and the list grows with every new market Luna enters.

CE REDEuropean Union

RoHSEuropean Union

WEEEEuropean Union

UKCAUnited Kingdom

CA65USA

UAE TDRAUnited Arab Emirates

UAE RoHSUnited Arab Emirates

Japan MICJapan

RCMAustralia / NZ

FCCUSA

WERCJapan

German WEEEGermany

Certification	Region	What it covers
CE RED	European Union	EU Radio Equipment Directive: radio, safety, and EMC conformity for wireless devices sold in the EU.
RoHS	European Union	Restriction of Hazardous Substances: limits lead, mercury, cadmium and other hazardous materials.
WEEE	European Union	Responsible end-of-life collection and recycling compliance for electronics.
UKCA	United Kingdom	UK Conformity Assessed: the mark for products placed on the Great Britain market.
CA65	USA · California	Proposition 65: warning and limits on exposure to listed chemicals in California.
UAE TDRA	United Arab Emirates	Telecommunications regulatory approval for wireless devices in the UAE.
UAE RoHS	United Arab Emirates	UAE restriction of hazardous substances, aligned to EU RoHS.
Japan MIC	Japan	Ministry of Internal Affairs radio certification (Giteki) for Japan.
RCM	Australia / NZ	Regulatory Compliance Mark: electrical safety and EMC/radio compliance.
FCC	USA	Federal Communications Commission authorization for radio-frequency emissions.
WERC	Japan	Registration for compliant electronics recycling in the Japanese market.
German WEEE	Germany	German national WEEE (ElektroG / stiftung ear) e-waste take-back registration.

Luna plans your day. Accuracy is where that promise begins.

We are at some of the best results in the world today, and we are not stopping here. We will keep building and improving this, together with you and with the community's feedback.

Accuracy you can trust,at every layer.

We measure against instruments that set the standard.

Explore the stack

It starts with the signal

Then we make it true for you

We take it everywhere you go

And we keep learning, in real time

Held to a responsible standard

Held to a responsible standard

Accuracy you can trust,
at every layer.