The questions our customers ask before, during, and after buying. If yours isn't here, just ask.
Daysy is designed for cycles between 19 and 40 days. If your cycles usually fall in that range, even irregularly, Daysy will learn them, typically in 2 to 3 full cycles. Women with PMOS and postpartum return-to-cycle are some of our longest-running customers. Take the 2-minute fit check if you want a personalized answer.
No. Daysy is $249 during the Spring Sale (regularly $299), one time. The DaysyDay companion app is free, forever. No refill strips. No tiered features.
No. Daysy is a cycle monitor, a tool for observing where you are in your cycle. It is not classified or marketed as a contraceptive device. How you apply the information is your decision, ideally with your provider. If you need contraception, please talk to your doctor. Read the full honesty page.
Daysy is a Class I registered medical device. Lady-Comp is FDA 510(k) cleared, a higher standard. "Registered" and "cleared" and "approved" are three different FDA labels. The science page explains each one.
Same sensor, same algorithm, different form factor and feature set. Daysy syncs to an app. Lady-Comp is app-free with a built-in display and FDA 510(k) clearance. Pearly is the smallest, app-free, travel-ready. Full comparison here.
Typically 2 to 3 full cycles. During this time the algorithm learns your specific patterns and you'll see more yellow lights than normal. After the learning phase, results stabilize. If after two full cycles your results aren't stabilizing, our 30-day money-back guarantee means a full refund.
It's fine. The algorithm is designed for real life. Occasional missed readings don't reset the learning phase or invalidate your cycle data. Just take it the next morning. If you miss multiple days in a cycle, that cycle's resolution may be lower.
Limited. Daysy depends on a relatively consistent wake time. If your sleep schedule varies dramatically (overnight shifts, rotating schedules), the BBT signal becomes less reliable. We say this honestly: if you're a shift worker, Tempdrop or Inito may be a better fit.
A single charge lasts about a month with daily use. Charging takes about two hours via the included USB cable.
Free USPS First Class shipping from our Maryland warehouse, within 24 hours of order. Arrival in 3 to 5 business days for most of the US.
30 days, full refund, free return shipping from anywhere in the US, no questions asked. Send it back if it isn't right for you.
Two-year manufacturer warranty against defects. If your Daysy stops working through no fault of yours, we replace it.
Yes. Most HSA/FSA plans recognize Daysy as an eligible health expense. We provide an itemized receipt suitable for reimbursement.
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