Terms of use
Pillow Math is a set of free sleep calculators and articles. The terms for using it are published on this site.
Not medical advice
The calculators do arithmetic with the times you enter, and the articles explain the numbers behind it. None of it is medical advice. If a sleep problem worries you, talk to a doctor. The disclaimer covers this in full.
Your data
The two forms on the site are the optional UP beta waitlist and the contact form. What the site stores on your device, what its cookie banner sends, and what those two forms keep and for how long is on the privacy page.