CalculatorHow much fiber do you need a day?
The recommendation is 14 g of fiber per 1,000 calories. Enter your details and the calculator estimates your calories, turns that into a fiber target, and builds a day of real food that gets there.
What 25 g looks like in a day
A sample day built from the FiberUp database. Servings are the real ones in the app, and every food links to its own page.
Day total0 g
Frequently asked questions
How much fiber should I eat per day?
The Institute of Medicine sets an adequate intake of 14 grams for every 1,000 calories you eat. For a typical adult that works out to 25 g a day for women and 38 g for men under 50, and 21 g and 30 g after 50. The daily value printed on US nutrition labels is 28 g. Most adults get about 15 g.
Why does the calculator ask for height and weight?
Because the fiber recommendation is tied to calories, and calories are tied to body size and activity. The calculator estimates your daily calories with the Mifflin-St Jeor equation, then applies 14 g per 1,000 calories. A tall, active man and a small, sedentary woman get very different numbers, which the flat 25 g and 38 g figures hide.
Is more fiber always better?
Up to a point. Intakes of 40 to 50 g from whole foods are normal in traditional diets and well tolerated when the increase is gradual. Jumping from 15 g to 40 g in a week usually causes gas and bloating, so add about 5 g every few days and drink more water.
Does pregnancy change the number?
Yes. The adequate intake rises to 28 g during pregnancy and 29 g while breastfeeding, and the calculator uses whichever is higher, that figure or your calorie-based estimate.
Do children need the same amount?
No. Children need less in absolute terms: roughly 19 g at ages 1 to 3, 25 g at 4 to 8, then 26 to 31 g for 9 to 13, and 26 to 38 g for teens depending on sex. This calculator is for adults.
Hit the number every day
FiberUp sets this goal for you and shows a daily ring so you know where you stand by lunch. On iPhone and Android.
Calories are estimated with the Mifflin-St Jeor equation and an activity factor. Fiber targets follow the Institute of Medicine adequate intake of 14 g per 1,000 kcal (Dietary Reference Intakes, 2005). General nutrition information, not medical advice. Increase fiber gradually and talk to a clinician if you have a digestive condition.
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