Eighteen hours fasting, six eating — a step up from 16:8 for people whose rhythm is settled. Enter when you stopped eating and find out exactly when your window opens.
Your 18-hour window opens at —
Why people move to 18:6: once 16:8 feels uneventful, two more hours is a small stretch. Many people find the extra two hours land during sleep or the busy morning — the easiest hours to extend.
A typical 18:6 day (last meal 8pm): your window opens at 2pm. The hungriest stretch is often the late morning — for many people it passes in a wave of about 20 minutes.
Fluent Fast never tells you to push past your plan. Eighteen hours is a routine, not a record.
Not inherently — the best schedule is the one you can repeat daily. Many people graduate from 16:8 to 18:6 once the shorter window feels easy.
Black coffee, plain tea, and water are the standard fasting-friendly drinks. Anything with meaningful calories technically breaks the fast.
Drop back to 16:8 without guilt. Consistency beats duration — a kept 16 beats a broken 18 every time.
Save your schedule in Fluent Fast — free forever, no account needed.
Open in Fluent Fast →More calculators: 16:8 · 18:6 · 20:4 · OMAD · Fast end time · Eating window
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