Every packaged food sold in the United States carries a Nutrition Facts label, standardized by the FDA. Once you know what each section means, it takes about ten seconds to read one — here's how.
Start with the serving size
Everything else on the label is calculated per serving, not per package. A bag of chips might list "about 8 servings per container" — if you eat half the bag, double every number on the label. This is the single most common place people misread a label: the calorie count at the top is for one serving, not the whole thing.
Calories
The large number just below the serving size is calories per serving. It tells you how much energy that serving provides, independent of anything else on the label — it isn't adjusted for how filling or nutritious the food is.
% Daily Value (%DV)
Most nutrients on the label show a percentage next to the amount. This is the % Daily Value — how much one serving contributes toward a general 2,000-calorie-a-day reference diet. As a rule of thumb: 5% DV or less is considered low for that nutrient, and 20% DV or more is considered high. This is useful for quickly comparing two products, even if your own calorie needs differ from 2,000.
Nutrients to generally look for less of
Saturated fat, sodium, and added sugars are the three nutrients most public health guidance suggests keeping an eye on. They're listed with their own %DV lines specifically so they're easy to compare across products without doing any math.
Nutrients to generally look for more of
Dietary fiber, vitamin D, calcium, iron, and potassium are called out specifically on the modern label because typical diets tend to run short on them. A higher %DV here is generally the more favorable direction.
Added sugars vs. total sugars
The label separates "Total Sugars" from "Includes Xg Added Sugars." Total sugars includes naturally occurring sugar (like the fructose in fruit); added sugars is only sugar added during processing. A plain banana, for example, has real, naturally occurring sugar with no added sugars line at all — worth keeping in mind when comparing a whole food to a packaged one.
Ingredients list, separately
The ingredients list sits below the Nutrition Facts panel and is ordered by weight, heaviest first. It's a different piece of information from the nutrition panel itself — useful for spotting a specific ingredient, rather than for the numeric breakdown.
Putting it together
Reading a label well is really just: check the serving size first, look at the calorie count for that serving, then scan the %DV column to see which nutrients are unusually high or low relative to that 2,000-calorie reference point. That's the whole system.