How Much Fiber Per Day Calculator
How much fiber per day calculator — This tool helps you determine your optimal daily fiber intake based on your age, gender, body metrics, activity level, and dietary preferences. It compares guidelines from the USA (IOM), UK (NHS), WHO, EU (EFSA), Australia, Canada, Japan, China, and India, giving you a personalized recommendation with a visual breakdown. Fiber supports digestive health, heart health, and blood sugar regulation. Use this calculator to align your diet with global standards.
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grams
daily fiber recommendation
Based on your profile & selected standard
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Est. Daily Calories
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Fiber per 1000 kcal
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USA (IOM) ref
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WHO
📊 Factor Breakdown
Age—
Gender—
Activity—
Calorie needs—
Dietary preference—
Primary standard—
Frequently Asked Questions
What is the recommended daily fiber intake?
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The recommended daily fiber intake varies by age, gender, and country. In the USA, the IOM recommends 25 g/day for women and 38 g/day for men aged 19–50. The WHO suggests 25–35 g/day for adults, while the UK NHS recommends 30 g/day. This calculator personalizes the recommendation based on your profile and compares multiple global standards.
How does activity level affect fiber needs?
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Higher activity levels increase your caloric needs, and fiber intake is often recommended at 14 g per 1000 calories consumed. More active individuals typically need more total fiber, though the proportional recommendation (g per 1000 kcal) remains consistent. This calculator adjusts your fiber target based on your estimated energy expenditure.
Which country has the highest fiber recommendation?
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Among major guidelines, the USA (IOM) recommends up to 38 g/day for adult men, which is among the highest. The UK NHS recommends 30 g/day for adults, and WHO suggests 25–35 g/day. Australia recommends 30 g/day for men and 25 g/day for women. Japan and EU guidelines are slightly lower at 20–25 g/day. This calculator shows all these standards side-by-side.
Does dietary preference change my fiber recommendation?
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Your dietary preference does not change the recommended fiber target, but it influences how easily you can meet it. Vegetarians and vegans typically consume more fiber naturally from plant-based foods. This calculator includes diet preference to provide context and suggest that plant-based eaters may already be closer to their fiber goal.
How is the calorie-based fiber recommendation calculated?
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We use the Mifflin-St Jeor equation to estimate your Basal Metabolic Rate (BMR) based on age, gender, weight, and height. Then we multiply by your activity factor to get Total Daily Energy Expenditure (TDEE). The fiber recommendation is calculated as 14 g of fiber per 1000 calories of TDEE, which is a widely used dietary guideline.