How much fiber do you need each day?
This fiber intake calculator gives your recommended daily fibre target and then lets you log a day of eating to see how close you are. Choose the US and Canada reference (by age and sex, including pregnancy and breastfeeding), the UK SACN recommendation, the EU adequate intake for adults, or a target based on your energy intake in grams of fibre per 1,000 kcal. Spelling varies, fiber in the US and fibre in the UK, India and Australia, and the numbers are the same.
The food log covers 29 common foods, from apples and oats to dal, chickpeas, roti and chia seeds, with fibre values from the USDA FoodData Central database. If you also track energy, protein and carbs, the calorie calculator, protein calculator and net carbs calculator use the same food data.
How to use the Fiber Intake Calculator
- Pick the recommendation you want to follow, then enter your age, sex and, if relevant, pregnancy or breastfeeding. Or choose the energy method and type your calories.
- Read your daily fibre target and the source it comes from.
- In the log, enter how many servings of each food you ate. Half servings are fine (0.5).
- Use Other fibre for packaged foods, where the label gives the grams. The bar and the numbers show what is left to reach the target.
Fiber Intake Calculator features
Several reference systems
US/Canada, UK, EU and an energy-based option, so you can see how much the guidance differs.
Pregnancy and breastfeeding
The US values of 28 g and 29 g a day are built in.
Food log with real data
Fibre per serving from USDA values for fruit, vegetables, grains, pulses, nuts and seeds, with Indian staples such as roti and dal.
Progress at a glance
A bar, the grams still to go, your top three fibre sources and a gentle tip on increasing fibre slowly.
Editable energy rule
Change the grams per 1,000 kcal to follow another guideline, such as the 2020 Indian summary of about 15.
The recommendations behind the numbers
The US and Canadian Adequate Intake (National Academies, 2005) is 14 g of fibre per 1,000 kcal. In practice it is a set of values by age and sex: 25 g for adult women and 38 g for adult men aged 19 to 50, then 21 g and 30 g from age 51, 28 g in pregnancy and 29 g while breastfeeding. UK guidance from SACN (2015) is 30 g a day for adults, measured by the AOAC method, with 25 g for ages 11 to 15, 20 g for 5 to 10 and 15 g for 2 to 4. The European Food Safety Authority (2010) judged 25 g a day adequate for adult bowel function.
India's ICMR-NIN 2020 requirements set fibre relative to energy, and secondary summaries of the short report give about 30 g per 2,000 kcal. I could not read the full table, so the energy mode keeps the figure editable instead of hard-coding it. All values were checked on 24 October 2026.
| Group | US/Canada (AI) | UK (SACN) |
|---|---|---|
| Women 19–50 | 25 g | 30 g |
| Men 19–50 | 38 g | 30 g |
| Women 51+ | 21 g | 30 g |
| Men 51+ | 30 g | 30 g |
| Children 4–8 (US) / 5–10 (UK) | 25 g | 20 g |
Getting more fibre safely
Most people eat well under the target. Beans, lentils, whole grains, berries, pears, nuts and seeds give the most fibre per serving. Raise your intake by a few grams every few days and drink plenty of water, because a sudden jump can cause gas and bloating. Fibre needs are also lower or different for some conditions, such as flare-ups of inflammatory bowel disease or a low-residue diet, so follow your clinician's advice. This calculator provides general information and food values are averages that vary by brand and cooking.
Fiber Intake Calculator FAQ
How much fiber should I eat a day?
For US adults the Adequate Intake is 25 g for women and 38 g for men aged 19 to 50, and 21 g and 30 g after 50. UK guidance for adults is 30 g a day.
How do I calculate fibre from calories?
Multiply your daily calories by 14 g per 1,000 kcal: 2,000 kcal gives 28 g. The calculator's energy option does this and lets you change the rate.
Is fibre the same as fiber?
Yes. Fiber is the US spelling and fibre the UK, Indian and Australian one. This tool uses the same data either way.
Why is the UK target higher than the US one for women?
The UK figure is measured by the AOAC method, which counts more of the fibre, so 30 g in the UK is not directly comparable with a US value.
Can I eat too much fibre?
There is no set upper limit, but very quick increases can cause bloating, gas and loose stools, and large amounts can reduce the absorption of some minerals. Increase gradually.
Which foods are highest in fibre?
Chia and flax seeds, beans, lentils and split peas, oats and barley, raspberries, pears and nuts are among the richest. Enter servings in the log to compare.