Find your rhythm.

A little clockwork.

For a 16:8 schedule, a last meal ending at 20:00 means the 16-hour fasting window ends at 12:00 the following day. The remaining eight hours form the eating window.

The calculator shows clock-time arithmetic for a repeating 24-hour day. It does not account for daylight-saving changes or travel between time zones. Your entries stay in this page and are not saved or sent to us.

Choose with care.

A schedule is not a prescription. This tool cannot decide whether fasting is appropriate for you, and a longer window is not automatically better. Read the safety context and speak with a qualified clinician before changing how you eat.

Take your timer with you.

Reset keeps track of your chosen window, reminders and history on Android. The schedule here is a preview; set your window in the app after installing.