Hormones produce measurable physiological effects across your body, continuously. Progesterone raises your body temperature, shifts your heart rate, and alters your sleep architecture. Estrogen modulates cardiovascular tone and heart rate variability. Clair's multi-modal sensor array captures over 130 biomarkers spanning cardiovascular, thermoregulatory, autonomic, electrodermal, and other domains, then uses machine learning models trained against clinical-grade hormone measurements to decode the combined pattern into continuous hormonal insights.

Other wearables are fitness and recovery platforms. Their algorithms treat the hormonal variations in your data as noise to be smoothed over. A woman's HRV dropping 12% in her luteal phase looks like a recovery problem to a fitness algorithm. Clair was built from the ground up to treat female hormonal physiology as the primary signal. We use proprietary sensing modalities, extract 130+ biomarkers, and train models on paired wearable-and-hormone data to decode what your body is actually telling you.

Clair tracks estrogen, progesterone, LH (luteinizing hormone), and FSH (follicle-stimulating hormone). Each produces a distinct multi-system physiological signature that our sensor fusion models are trained to recognize.

Our prototype was validated on 40+ women across 127 complete menstrual cycles, achieving 94.1% accuracy in cycle phase classification from wearable data alone, with no blood draws or user input required. LH surge detection reached 87% sensitivity with timing accuracy within approximately one day. We are launching an independent clinical trial through the Stanford Gladstone BeeHive Initiative to validate our production hardware under rigorous oversight. Read more about our science on the blog.

Yes. Unlike calendar-based predictions, Clair tracks your actual cycle as it unfolds by monitoring real-time physiological signals. Our current accuracy on irregular cycles is 84.3%, compared to 95.2% for regular cycles. For context, most existing methods struggle or do not attempt to operate on irregular cycles at all. Improving performance for this population is a primary objective of our expanded clinical studies.

Clair 1.0 launches as a general wellness device, which does not require FDA clearance. It provides cycle phase tracking, hormonal trend insights, and wellness metrics. Clair 2.0 will pursue FDA 510(k) clearance to enable medical-grade claims, including quantitative hormone reporting. Both versions share the same hardware, and every Clair 1.0 device will receive the 2.0 upgrade over the air at no additional cost once cleared.

Clair uses a privacy-first, edge-first architecture. All AI processing happens on your phone. Your biometric data never leaves your device, and we never see it. If you opt into cloud backup, your data is encrypted with a passphrase only you know (zero-knowledge encryption). We architecturally cannot access your health data. Read more about our privacy approach on the blog.

Early Bird pre-orders are 20% off MSRP: $295 instead of $369 (a $74 savings). The price is paid in full at checkout and includes the Clair wearable device plus 6 months of Clair Pro included (then $9.99/mo Pro or $5.99/mo Core). 100% refundable until we ship.

We are targeting late 2026 for shipping to the US and Canada, and mid 2027 for the rest of the world. Early Bird customers get priority shipping and regular updates on our progress. We will reach out before launch to confirm your shipping address and preferences.

Yes. Clair is pre-approved for HSA/FSA payment through our partner TrueMed. You can use your pre-tax health savings to pay the full Early Bird price of $295 during checkout. TrueMed handles eligibility verification and payment processing.