Free tool
Fiber Calculator: How Much Fiber Do You Need a Day?
Find your daily fiber target by age and life stage or from your calorie intake, then tick common foods to see how close you are.
This page is for general education and is not medical advice. Talk with your clinician or a registered dietitian before major diet changes or starting supplements, especially if you take medication, are pregnant, or have a chronic condition. See our medical disclaimer.
Find your daily fiber target
Choose a group or enter your calories to see your fiber target.
Optional: tick the foods you ate today (one serving each) to see how close you are
Fiber targets by age and life stage
| Group | Fiber (g a day) |
|---|---|
| Children 1 to 3 | 19 |
| Children 4 to 8 | 25 |
| Boys 9 to 13 | 31 |
| Girls 9 to 13 | 26 |
| Boys 14 to 18 | 38 |
| Girls 14 to 18 | 26 |
| Men 19 to 50 | 38 |
| Women 19 to 50 | 25 |
| Men 51 and older | 30 |
| Women 51 and older | 21 |
| Pregnancy (14 to 50) | 28 |
| Breastfeeding (14 to 50) | 29 |
Where the fiber is
Beans, lentils and split peas lead per serving, followed by berries, peas, whole grains, avocado, chia and other seeds. See the full ranked table in our high-fiber foods list, and our guides to fiber, gut health and weight and healthy meal prep.
Common questions
How much fiber should I eat a day?
The National Academies Adequate Intake is 25 g for women and 38 g for men aged 19 to 50, and 21 g and 30 g for those 51 and older. These are based on 14 g of fiber per 1,000 calories, the benchmark used in the Dietary Guidelines for Americans. The Daily Value on food labels is 28 g.
Why do most people fall short?
The Dietary Guidelines for Americans identify dietary fiber as a nutrient most Americans do not get enough of. Beans, lentils, vegetables, fruit, whole grains, nuts and seeds are the main sources.
How do I add fiber without gas and bloating?
Increase slowly over a few weeks, drink enough fluids, and spread fiber through the day. Rinsing canned beans can help. People with IBS may want dietitian guidance; see our low-FODMAP guide.
Should I count total fiber or soluble fiber?
The targets here are for total dietary fiber. Most plant foods supply a mix of soluble and insoluble fiber, so eating a variety is the practical approach.
What if I have a digestive condition?
People with a bowel narrowing, active inflammatory bowel disease flares, gastroparesis, or who have been told to follow a low-residue diet should follow their care team’s fiber advice.
Cite or link to this tool
HealAtlas Team. Fiber Calculator. HealAtlas. https://healatlas.com/nutrition-calculators/fiber-calculator/
Related on HealAtlas
Sources
- National Academies: Dietary Reference Intakes (DRIs): RDAs and AIs for total water and macronutrients
- National Academies Press: Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids (2005)
- Dietary Guidelines for Americans, 2020-2025 (USDA/HHS)
- Harvard T.H. Chan School of Public Health, The Nutrition Source: Fiber
- FDA: Daily Value on the Nutrition and Supplement Facts Labels
- USDA FoodData Central (SR Legacy) nutrient data