Quickly determine your recommended daily dietary fiber intake based on your age and gender to support optimal digestive health, weight management, and overall wellness.
Dietary fiber is an essential plant-based nutrient that your body cannot digest. Unlike other carbohydrates that break down into sugar, fiber travels through your digestive system largely intact. It plays a vital role in maintaining good health by promoting regular bowel movements, feeding beneficial gut bacteria, and helping to control blood sugar levels and appetite.
The Institute of Medicine (IOM) provides the following evidence-based recommendations for daily fiber intake for adults:
| Age Group | Recommended Fiber (grams/day) |
|---|---|
| Men (19–50 years) | 38 grams |
| Women (19–50 years) | 25 grams |
| Men (51+ years) | 30 grams |
| Women (51+ years) | 21 grams |
Disclaimer: This calculator provides general recommendations. Individual needs may vary, especially for those with certain medical conditions. Always consult a healthcare professional for personalized dietary advice.
Knowing your number is half the job — the other half is eating it. Most adults in the U.S. get only about 15 grams a day, roughly half the recommended amount. The good news: a few deliberate swaps close the gap fast, because fiber is concentrated in a short list of foods.
| Food (serving) | Fiber (approx.) |
|---|---|
| Lentils, cooked (1 cup) | 15 g |
| Black beans, cooked (1 cup) | 15 g |
| Chia seeds (1 oz / 2 tbsp) | 10 g |
| Avocado (1 whole) | 10 g |
| Raspberries (1 cup) | 8 g |
| Pear, with skin (1 medium) | 6 g |
| Quinoa, cooked (1 cup) | 5 g |
| Broccoli, cooked (1 cup) | 5 g |
| Apple, with skin (1 medium) | 4.5 g |
| Oats, dry (1/2 cup) | 4 g |
| Whole-wheat bread (2 slices) | 4 g |
| Almonds (1 oz) | 3.5 g |
Two types, both useful. Soluble fiber (oats, beans, lentils, fruit) dissolves into a gel that helps lower LDL cholesterol and steadies blood sugar. Insoluble fiber (whole wheat, vegetable skins, nuts) adds bulk and keeps digestion moving. You do not need to track them separately — a varied plant-heavy diet covers both. Harvard's Nutrition Source has a thorough fiber reference if you want the deeper science.
Ramp up gradually. Jumping from 15 g to 35 g overnight is a recipe for gas and cramping. Add 5 g every few days, and drink extra water as you go — fiber needs fluid to do its job. Simple wins: berries or chia on breakfast, lentils or beans at lunch, and whole fruit instead of juice for snacks.
Maintained by Live Fitness Check. Last updated: August 24, 2026. How we test our calculators .
Estimates a daily fiber target using age and sex.
The calculator maps the entered age and sex to the dietary fiber target configured for that group. The calculation uses age and sex.
Individual needs can differ with total calorie intake, gastrointestinal conditions, pregnancy and clinician-directed diets. Use the number as an estimate and consider professional advice when the result may affect health, treatment, pregnancy, nutrition, exercise safety or another important decision.
