Fiber Intake Calculator

How much fiber do you need?

A common nutrition target is about 14 g of fiber per 1,000 calories. Adult adequate-intake targets are also commonly listed by age and sex, which is why the calculator shows both a calorie-based target and an age-sex target.

The result uses the higher of those two targets as the practical goal. This keeps a low-calorie diet from producing an unrealistically low fiber recommendation.

Example: if you eat 2,000 calories, the calorie-based rule gives 28 g/day. If you are a 35-year-old man, the age-sex target is 38 g/day, so the calculator uses 38 g as the recommended target.

Fiber targets by age and sex

These reference targets are useful starting points, but personal tolerance and total diet quality matter too.

How to close a fiber gap

The easiest approach is to add one fiber-rich food at a time and keep fluids consistent. Beans, lentils, oats, chia, berries, apples, potatoes with skin and vegetables all help.

If you currently eat very little fiber, even one extra serving of beans or oats per day can move the trend meaningfully without requiring a full diet overhaul. The result card shows a suggested weekly increase so the target feels reachable.

• Add oats, berries or chia at breakfast.
• Use beans or lentils in one meal per day.
• Choose potatoes with skin, whole grains or vegetables as carb sources.
• Add fruit instead of only relying on fiber supplements.

Increase gradually to avoid bloating

If your current intake is much lower than your target, add about 3-5 g per day each week until you reach a sustainable intake.

A gradual increase gives your gut microbiome and digestion time to adapt. Increasing water intake can also help fiber move comfortably through the digestive tract.

Soluble vs insoluble fiber

Soluble fiber forms a gel-like texture in water and is found in foods such as oats, beans, lentils, apples and chia. It can help with fullness and the overall quality of a meal.

Insoluble fiber adds bulk and is common in wheat bran, many vegetables, whole grains and skins. Most high-fiber foods contain a mix, so you usually do not need to micromanage the type if your diet includes varied plants.

High-protein diets and fiber

Protein goals often push people toward lean meat, dairy and protein powders. Those foods can be useful, but most contain little or no fiber.

If you are using a protein calculator or recomposition plan, pair protein anchors with high-fiber carbohydrate sources and vegetables so digestion, fullness and micronutrients do not suffer.

Food examples that add about 5 grams of fiber

Exact values vary by brand and portion size, but these examples show how small additions can close a daily fiber gap.