The 18:6 schedule

What 18:6 means

18 hours not eating, 6 hours when meals happen, together making up the full 24 hour day. It's the same idea as 16:8, just with the ratio shifted: a shorter eating window and a longer stretch on either side of it.

Some people move to 18:6 after getting comfortable with 16:8 and wanting a narrower window. Others start here directly because a 6 hour window fits their day better than an 8 hour one, for example if lunch and dinner are the two meals that matter most and breakfast was never really part of the routine.

How the timer helps

A narrower window makes the clock matter more, not less. With only 6 hours open, knowing exactly when that window starts and when it's about to close is more useful than a rough estimate. WhenCanIEat counts down to the open, counts up once you're inside the window, and gives you a clear signal as the window is about to close, so you're never caught guessing how much time is left.

An example day

Here's an 18:6 schedule with an eating window from 1:00 PM to 7:00 PM:

Time	What's happening
7:00 PM (previous day)	Eating window closes, fast begins
Overnight	Fast continues through sleep
9:00 AM	Timer shows the countdown to your window opening
1:00 PM	18 hour fast complete, eating window opens
1:00 PM to 7:00 PM	Eating window is open
7:00 PM	Window closes, next fast begins, streak updates

As with any schedule, the window can sit anywhere in your day. A morning version might run 8:00 AM to 2:00 PM instead.

Adjusting from 16:8

If you're moving over from 16:8, the simplest change is shaving an hour off each end of your existing window rather than picking a whole new schedule. The App makes this a two tap change: switch the preset to 18:6 and confirm your window start time.

Getting started

Open WhenCanIEat, choose the 18:6 preset, set your window start time, and start your first fast. Free to try, no account needed.