Fiber Intake Calculator
Find out how much dietary fiber to aim for each day. The calculator uses the Institute of Medicine's Adequate Intake by age and sex, or 14 grams per 1,000 calories if you enter your daily calories, and compares it with what you eat now.
Leave empty to use the Adequate Intake for your age
Check food labels or a food diary app
How to use the Fiber Intake Calculator
- Enter your age and sex, and life stage if pregnant or breastfeeding.
- Add your daily calories for a personal target, or leave it empty to use the standard Adequate Intake.
- Optionally enter the fiber you eat now to see the gap.
- Read your target and the per-meal amount.
- Use the food table to plan meals that reach it.
How the fiber target is calculated
- Calorie-based target = 14 g × daily calories ÷ 1,000. Example: 2,200 kcal → 14 × 2.2 = 30.8 g a day.
- Adequate Intake (AI): the Institute of Medicine applied the same 14 g per 1,000 kcal to typical calorie intakes for each age and sex group, giving the table below.
| Age | Males (g/day) | Females (g/day) |
|---|---|---|
| 1–3 years | 19 | 19 |
| 4–8 years | 25 | 25 |
| 9–13 years | 31 | 26 |
| 14–18 years | 38 | 26 |
| 19–50 years | 38 | 25 |
| 51 years and older | 30 | 21 |
| Pregnancy | — | 28 |
| Breastfeeding | — | 29 |
Easy ways to add fiber
- Swap white bread, rice and pasta for whole grain versions.
- Add half a cup of beans or lentils to soups, salads and sauces (about 7–8 g).
- Keep the skin on fruit and potatoes, and choose whole fruit over juice.
- Stir a tablespoon of chia or ground flax into yogurt or oatmeal.
- Increase slowly and drink water as you go.
Fiber values in the calculator's food table are approximate, from USDA FoodData Central; check labels for packaged foods.
Frequently asked questions
How much fiber should I eat per day?
The US Institute of Medicine sets an Adequate Intake of 38 g a day for men aged 19–50 and 25 g for women aged 19–50; 30 g and 21 g for those over 50. Pregnancy and breastfeeding raise it to 28 g and 29 g. The UK recommends 30 g a day for adults.
What is the 14 g per 1,000 calories rule?
The Adequate Intake was set at 14 grams of fiber for every 1,000 calories eaten, the amount linked with lower heart disease risk in studies. On a 2,000 kcal diet that is 28 g a day; on 2,500 kcal it is 35 g.
How much fiber do children need?
The Adequate Intake is 19 g for ages 1–3 and 25 g for ages 4–8. From 9–13 it is 31 g for boys and 26 g for girls, and from 14–18 it is 38 g for boys and 26 g for girls. There is no set amount for babies under 1.
Is it possible to eat too much fiber?
No upper limit has been set, but a sudden large increase can cause gas, bloating and cramps. Increase fiber gradually over a few weeks and drink enough fluids. Very high intakes are rarely a problem from normal food.
What are the best sources of fiber?
Beans, lentils and peas are among the richest sources (around 15 g per cooked cup), followed by whole grains, seeds such as chia and flax, nuts, berries, pears, apples with the skin and vegetables such as broccoli and Brussels sprouts.
What is the difference between soluble and insoluble fiber?
Soluble fiber (oats, beans, apples) dissolves into a gel and can help lower cholesterol and steady blood sugar. Insoluble fiber (whole wheat, bran, vegetable skins) adds bulk and helps regularity. Most plant foods contain both.