Fasting guide
16:8 intermittent fasting
Updated October 11, 2026 · MyPlate
16:8 is a clock, not a calorie target. You fast for 16 hours and eat within 8. A typical window is 12:00 to 20:00. You still need a daily calorie number. If weight loss is the goal, that number has to sit under your TDEE. The fasting schedule does not replace the deficit.
Intermittent fasting only tells you when. The foods and the amounts tell you how much energy you ate. People like 16:8 because it often means skipping breakfast and eating lunch and dinner, which some find easier than grazing. Other people get very hungry and then overshoot inside the window. Both outcomes are about the total, which is why this page sits next to the calorie tools instead of promising a result from the clock alone.
A sample clock
| Time | What happens |
|---|---|
| 20:00–12:00 | Fast. Water, black coffee, or plain tea. |
| 12:00 | First meal. Start the day's calorie log here. |
| 16:00 | Optional second meal or a snack you actually weigh. |
| 19:30 | Last meal, finished before the window closes. |
| 20:00 | Window closes. The fast starts again. |
Move the block earlier or later if your workday demands it. The length of the fast stays 16 hours. The intermittent fasting calculator prints the times from the hour you choose. The longer guide is intermittent fasting schedules, which also covers 18:6, 20:4, and 5:2.
Worked meals inside the window
Keep the same daily target you would use on calories to lose weight. Here is one lunch built only from USDA servings: 100 g roasted skinless chicken breast (165 kcal, FDC 171477), 1 cup cooked white rice (205 kcal, FDC 168878), and 1 cup chopped raw broccoli (24 kcal, FDC 747447). The sum is 394 kcal. A later plate of 1 cup cooked oatmeal (166 kcal, FDC 173905) and one large raw egg (72 kcal, FDC 171287) is 238 kcal. Together those two meals are 632 kcal. They are not a full day unless your target is that low, which for most adults it is not. Log the rest of the window the same way.
Black coffee does not add much. The chart lists brewed coffee at 2 kcal per cup (FDC 171890). A splash of whole milk does. Whole milk is 60 kcal per 100 g (FDC 746782). If you add milk, the fast is over and the calories belong in the log.
Common mistakes
- Eating "whatever" after noon because the fast felt hard. The window is not a free pass.
- Forgetting oil and sauces at the first meal. One tablespoon of olive oil is 119 kcal (FDC 171413).
- Setting the calorie target from BMR. Use TDEE. See BMR vs RMR vs TDEE.
- Starting 16:8 to manage a medical condition without asking the clinician who manages it.
Sources
- USDA FoodData Central IDs above, retrieved 11 October 2026.
- NHS weight-loss tips for the pace of loss, if that is why you are fasting.
Get a calorie target on the calorie calculator. The app is free to download, try every feature free, with a 3-day free trial.
Frequently asked questions
What is 16:8 intermittent fasting?
You go 16 hours without calorie-containing food or drink, then eat inside an 8-hour window. A common clock is noon to 8 pm.
Does 16:8 burn fat by itself?
The window changes when you eat. Fat loss still depends on eating under your TDEE across the day. Fasting can make that easier for some people and harder for others.
What can I have while fasting?
Plain water, and black coffee or plain tea if you are not adding milk or sugar. Brewed coffee in our chart is 2 kcal per cup before anything is added. Milk and sugar end the fast.
How many meals fit in 8 hours?
Two or three. The calorie total of those meals is what matters. Use the same daily target you would use without fasting.
Who should skip this schedule?
Anyone who is pregnant, has a history of disordered eating, or takes medication that must be taken with food should talk to a clinician first. This page is a schedule description, not medical advice.
Is there a calculator?
Yes. The intermittent fasting calculator turns a first-meal time into window times. Pair it with the calorie calculator.