How accurate is this estimate?

It is a friendly approximation based on average fiber values for each food group, not a precise measurement. Real values vary by the exact food and portion. Its job is to show you roughly where you stand and whether there is a gap worth closing.

What counts as a serving?

Roughly a piece of fruit, half a cup of cooked vegetables, one slice of whole grain bread or half a cup of cooked grains, half a cup of cooked beans or lentils, or a small handful of nuts or seeds.

What should I aim for?

A good general target is around 25 grams a day for women and 38 grams for men. If your estimate lands lower, adding a serving or two of beans, whole grains, or fruit is usually the easiest fix.

Verified formulaLast reviewed July 2026

Are You Getting Enough Fiber?

Estimate your daily fiber from what you actually eat, and see how close you are to a healthy target.

Your details

Fruit servings (per day)

Vegetable servings (per day)

Whole grain servings (per day)

Beans or lentils (per day)

Nuts or seeds (per day)

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Fill in your details to see your result.

A mathematical estimate based on validated equations, for education only. It is not a diagnostic tool.

The science

Most people have no idea how much fiber they eat in a day, and the honest answer is usually less than they think. Tell this estimator roughly how many servings of the main fiber-rich food groups you eat on a typical day, and it will give you a friendly estimate of your total, then show you how that compares with a healthy target. It is a rough guide, not a lab measurement, but it is often the moment the gap becomes clear and easy to close.

The formula

Sum of servings weighted by typical fiber per serving

Sources

1
Harvard T.H. Chan School of Public Health, The Nutrition Source: Fiber (nutritionsource.hsph.harvard.edu)
2
Dietary Guidelines for Americans (odphp.health.gov)

Common questions

This tool is for education only and is not a diagnostic device. Consult a licensed clinician before making health decisions.