Fasting schedules
A fasting schedule is a way of splitting the day into an eating window and a fasting window. This page lists examples adults often compare. It does not rank them, and it does not say which one is medically right for you.
The names below use a common convention: the first number is fasting hours, the second is eating hours. They add up to 24. If a chart you see elsewhere flips the order, check before you copy it.
12:12
Twelve hours of eating and twelve hours of fasting. For many people this is dinner finished in the evening and breakfast the next morning, with sleep in between. It is a useful reference point because it may already match real life.
Learning value: you practice noticing first and last bites without removing a meal you rely on. If 12 hours already feels difficult, that is information. It is a reason to pause and, if you are in a group named in the safety note, to talk with a clinician rather than to pick a longer number.
14:10
Fourteen hours fasting and ten hours eating. This is a modest change from 12:12. The eating window might run from 9:00 to 19:00, or from 8:00 to 18:00. One meal moves a little. The rest of the day stays recognizable.
People read 14:10 when they want a named pattern but do not want to skip a meal entirely. It is a fair page for cautious beginners, alongside 12:12. It is still only an example.
16:8
Sixteen hours fasting and eight hours eating. This is the pattern described most often in general articles. A common illustration is noon to 20:00. Another is 10:00 to 18:00. The full page is 16:8 fasting.
Eight hours is enough for two meals and, for some people, a snack. It is also enough to collide with family dinner or an early work start. Fit is about the clock you already live, not about willpower.
18:6
Eighteen hours fasting and six hours eating. The eating window is tight. Two meals can fit if they are close together. Three meals usually do not, unless they are small and planned. Read 18:6 fasting after shorter windows feel familiar. Do not treat 18:6 as the advanced version of a course.
What this page leaves out on purpose
Alternate-day fasting and 5:2 patterns change whole days, not just a daily clock. They are harder to explain safely in a short list, and they are easier to confuse with a crash diet. This site does not set calorie targets. If you see a plan that tells you to eat a very small number of calories on “fast” days, that is a different project, and it needs personal medical advice before anyone with a health condition considers it.
You may also see 20:4 in the schedule planner. It is there so the shape of a very short eating window is visible. Seeing it on a screen is not a reason to try it. Longer is not better.
How to compare them without turning it into a test
Pick the meal you least want to move. Put the eating window around that meal. Then see how long the overnight gap becomes. If the gap is 12 or 14 hours, you are looking at the gentler examples. If it is 16, you are looking at the common article example. If it is 18 or more, you are looking at a short eating window that deserves more caution, not more enthusiasm.
Use two ordinary days, not a holiday and not a sick day, when you write this down. Shift work, early sport, and shared meals all matter more than a neat diagram.
Drinks change the clock in practice. A milky coffee at 7:00 starts the eating window for many people who are trying to keep a zero-calorie fast, even if the “official” window was supposed to open at noon. Read what to drink while fasting before you commit a schedule to paper.
Changing a schedule
You can keep the same window, shorten the fast, or drop the pattern. Those are all coherent choices. Stretching the fast because a chart implies you should is the weak reason. Common fasting mistakes includes that one.
Hunger, the first meal, and movement each have their own guides: hunger, breaking a fast, and exercise. The definition page is what intermittent fasting is. Short answers are in the FAQ.
Safety
Safety. People who are pregnant, breastfeeding, under 18, have an eating disorder or a history of one, have diabetes or hypoglycemia, take medication, or have a heart, kidney, or other medical condition should talk with a healthcare professional before fasting. Stop a fast and get help if you feel faint, confused, or unwell.
The same examples, in a printable order, are in the beginner guide.