About
About SleepLabix
SleepLabix exists to make the 90-minute sleep cycle method easy enough to use every night — with no data uploaded and no accounts required.
Our mission
Waking up groggy is rarely about how long you slept. It is about where you woke up inside a sleep cycle. The 90-minute cycle method works by timing your alarm to fall between cycles rather than inside one. SleepLabix does that timing for you.
We built a tool that back-computes the best bedtime from a chosen wake time, and the best wake time from a chosen bedtime, so you can fall asleep and wake up at the cleanest points of your night.
Runs in your browser, no data uploaded
SleepLabix is a static tool. Every calculation happens locally in your browser using JavaScript — no times, no dates, and no personal sleep data are ever sent to a server. Your wake and bed times stay on your device, which is exactly how a private sleep calculator should work.
The only data this site ever stores is a small cookie that records whether you accepted the cookie notice. There is no login, no tracking of your sleep history, and nothing to install.
How the math works
Most adults sleep in repeating cycles of roughly 90 minutes. Each cycle moves through light sleep, deep sleep, and REM sleep, then loops again. Waking during deep sleep tends to cause sleep inertia — that heavy, disoriented feeling.
The calculator therefore starts from your wake time and subtracts whole cycles: bedtime = wake time − (cycles × 90 minutes + fall-asleep minutes). For example, five cycles take about 7.5 hours. Add a 15-minute fall-asleep latency and you would go to bed around 9:45 pm to wake refreshed at 7:00 am.
We treat 90 minutes as the average because real cycles vary slightly from person to person. The goal is a strong starting point, not a promise that you will never feel tired.
Local, transparent, and honest
SleepLabix has no sign-up, no subscription, and no company harvesting your habits. The estimates are general guidance — they are not medical advice. If you wrestle with insomnia or an ongoing sleep problem, the best move is always to talk to a qualified professional.
Questions, corrections, or partnership ideas? Reach out through our contact page.