Sleep diary: track your sleep, free and private
Log how many hours you slept each night. Your entries stay saved privately in your browser, with a simple chart to spot patterns.
Why keeping a sleep diary helps
A sleep diary is one of the simplest tools used in sleep medicine to spot patterns you'd otherwise miss — like a slow slide toward less sleep on weeknights, or a link between late caffeine and restless nights. Because your entries are stored only in your own browser, nothing is sent to a server, so this stays fully private.
Frequently asked questions
Is my sleep data private?
Yes — everything is stored only in your browser's local storage on your device. We never see or store your entries on our servers.
Will my entries be there if I come back tomorrow?
Yes, as long as you use the same browser on the same device and don't clear your browsing data.
How many nights should I track before I see patterns?
Two to three weeks is usually enough to reveal a meaningful trend, though even a week can highlight obvious issues like weekend sleep debt.
Want to go further?
Explore our guides and other calculators.