Intermittent Fasting Calculator

From the first meal, show when the eating window ends for a 16:8-style fast.

First meal hour

Minute

Eating window

Calculated Result

Fast from 20:00

Next eating window starts 12:00

Formula: 16:8 means 8 h eating; fast end = first meal + window

About this calculator

Sleep timing is on the sleep-cycle page. This tool only clocks the eating window. Medical fasting is not the same as a diet window.

FormulaFast end = first meal + eating-window hours

end = (start_minutes + eat_hours × 60) mod 24h.

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