Free, science-based sleep tools built with one purpose: to help people understand and improve their sleep — without subscriptions, ads or account sign-ups.
Most sleep advice online is generic, vague or buried behind paywalls. We believe that science-based sleep tools should be free, private and accessible to everyone — on any device, anywhere in the world.
Every tool on sleepcalculators.site runs entirely in your browser. No data is ever sent to a server. No account is required. No subscription. Just free, useful tools.
We have built 13 free sleep tools — from a bedtime calculator and chronotype quiz to a 30-day sleep tracker, sleep sounds player and shift-worker sleep optimizer. Every tool is built around published sleep science and is designed to give you a personalised, actionable result in under a minute.
We also maintain a free sleep science blog with 18 research-based articles covering everything from jet lag recovery to the difference between brown noise and white noise.
sleepcalculators.site is a property of Tools Master Hub — a web tools company based in Port Louis, Mauritius. We also operate simplepdftools.in (130+ free PDF tools) and gstcalculators.in (Indian financial calculators).
Our philosophy: build simple, build useful, build once, make it free.
Our tools and articles are based on published sleep research — including work from the American Academy of Sleep Medicine, the CDC sleep guidelines, the National Sleep Foundation, and peer-reviewed studies from institutions including the University of Pennsylvania, Harvard Medical School and the Stanford Sleep Medicine Center.
All educational content includes appropriate disclaimers. Our tools are not a substitute for medical advice. If you have persistent sleep difficulties, please consult a qualified healthcare professional.
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