What is "safety buffer"?
The number of days before you will derail on your goal, if you do absolutely nothing else between now and then. This is usually the number of days left in the countdown above your goal. In the image below, my countdown ends in 2 days, 7 hours, and 25 minutes, so we'd say I have 2 days of safety buffer on it.
A caveat for Do Less, Whittle Down, and weight goals
On these goal types, the safety buffer is sometimes more of an estimate than a statement of fact. For example, we might tell you that you've got 6 days of buffer on your eat less cookies goal. But we also can't prevent you from eating two boxes of cookies and blowing through an entire month's allowance in one really bad day. Or you may be doing great on your weight goal and have 40 safe days. But after an indulgent birthday dinner and a heavy weigh-in the next morning, now you're suddenly down to 3 safe days?
On those types of goals, it's best to pay attention to your hard cap limit instead. My goal below tells me I have 16 days of buffer — but if I get really lazy and start wasting 12 hours a day on the internet, I'll blow through my limit of 109.2 hours in about 10 days instead!
The highlighted number will tell you exactly how many cookies you can eat, or the highest weight you can be, before you fall off the road. If you stay below this, you'll be safe no matter what, even though your number of safe days may bounce around from day to day.