How to use the fat intake calculator
- Choose how to set your daily calories: work them out from your details, or enter a number you already know.
- If you're working them out, enter your units, sex, age, height, weight, activity level and goal.
- Choose how many meals you eat a day.
- Read your daily fat range, your saturated fat limit, and grams at several shares of calories.
How fat intake is calculated
The calculator applies two widely used guidelines. Total fat follows the National Academies' Acceptable Macronutrient Distribution Range for adults: 20% to 35% of calories. Saturated fat follows the Dietary Guidelines for Americans, 2025–2030, which say it generally should not exceed 10% of daily calories. Fat provides about 9 kcal per gram:
Daily calories come from the Mifflin-St Jeor equation times your activity factor, adjusted for your goal. A weight-loss goal never takes them below 1,200 kcal for women or 1,500 kcal for men. If you enter your own number instead, the calculator uses it directly.
Worked example
These are the calculator's defaults: a 35-year-old man, 175 cm, 70 kg, moderately active, maintaining weight, 3 meals a day.
- Daily calories: 1,623.75 × 1.55 = 2,516.8, so 2,517 kcal
- Lowest: 2,517 × 0.20 = 503.4 kcal ÷ 9 = 56 g
- Highest: 2,517 × 0.35 = 881.0 kcal ÷ 9 = 98 g
- Range: 56 – 98 g of fat a day, or about 19 to 33 g per meal
- Saturated fat: 2,517 × 0.10 = 251.7 kcal ÷ 9, so no more than 28 g a day
On a 2,000-calorie diet the same rules give 44 to 78 g of fat, with saturated fat up to 22 g.
Types of fat
| Type | Where it's found | Guidance |
|---|---|---|
| Monounsaturated | Olive oil, avocados, nuts, seeds | Good everyday choices |
| Polyunsaturated, including omega-3 | Oily fish, walnuts, flaxseed, many vegetable oils | Supplies essential fatty acids |
| Saturated | Fatty meat, butter, cheese, cream, coconut and palm oil | No more than 10% of calories |
| Trans | Some fried and baked goods | As little as possible; artificial trans fat has largely been removed from U.S. foods |
The 2025–2030 guidelines say healthy fats are found in many whole foods, including meat, eggs, seafood, nuts, seeds, full-fat dairy, olives and avocados. For cooking, they suggest prioritizing oils with essential fatty acids, such as olive oil. They also note that more research is needed on which fats best support long-term health, while keeping the 10% saturated fat limit. The easiest way to stay under it is to cut back on highly processed foods.
Fat isn't something to avoid. It carries vitamins A, D, E and K, supplies essential fatty acids your body can't make, and helps meals keep you full. Going below about 20% of calories for a long time makes it harder to get these nutrients. If you have high cholesterol, heart disease or diabetes, follow the fat targets your doctor or dietitian gives you, which may be lower. To set protein and carbs alongside fat, use the macro calculator.
Frequently asked questions
How many grams of fat should I eat a day?
For most adults, 20% to 35% of calories: 44 to 78 g on a 2,000-calorie diet, or 56 to 98 g at 2,517 kcal. Enter your details above to get the range for your own calorie needs.
How much saturated fat is too much?
The Dietary Guidelines say saturated fat generally shouldn't exceed 10% of daily calories. That's 22 g on a 2,000-calorie diet. People with high LDL cholesterol are often advised to aim lower, so check with your doctor.
Does eating fat make you gain weight?
Not by itself. Weight gain comes from eating more calories than you burn, whatever their source. Fat is calorie-dense at 9 kcal per gram, though, so large portions of oily or fried foods add up quickly.
Is a low-fat diet better for weight loss?
Studies comparing low-fat and low-carb diets with similar calories find similar weight loss over a year. Choose the pattern you can stick with, and keep saturated fat within the limit either way.
Related calculators
- Macro Calculator — Split your daily calories into grams of protein, carbs and fat, with preset or custom percentages and grams per meal.
- Calorie Calculator — Daily calories to maintain your weight, plus gradual targets for losing or gaining, using the Mifflin-St Jeor equation.
- Carbohydrate Calculator — How many grams of carbohydrate a day fit 45–65% of your calories, with low, middle and high levels and grams per meal.
- Protein Calculator — Daily protein in grams from your body weight, from the RDA minimum to targets for older adults and people who train.
Results are estimates for general information and are not medical advice. Talk to a doctor or other qualified professional about your health. See our disclaimer.