Fiber Intake Calculator
Target is the Institute of Medicine's Adequate Intake by age and sex — a widely-cited baseline, not a personal medical recommendation. Most US adults fall well short of it: government survey data puts average intake around 14g/day, less than half the typical target. If you're increasing your fiber intake, raise it gradually over 1–2 weeks and drink plenty of water — a sudden jump is the most common cause of bloating, gas, or cramping, not fiber itself. Per-serving values are commonly-cited averages; actual content varies by brand and preparation. This is general information, not medical advice.
Track today's fiber from common foods against your age- and sex-based daily target — no account, no paywall, no ads.
How it works
- Enter your sex and age to see your daily fiber target (Institute of Medicine Adequate Intake guideline)
- Log today's high-fiber foods by serving — lentils, avocado, oatmeal, and more
- See your running total, remaining gap to target, and a progress bar update live
Frequently asked questions
How much fiber do I actually need?
The Institute of Medicine's Adequate Intake guideline is 25g/day for women 50 or younger, 21g for women over 50, 38g for men 50 or younger, and 30g for men over 50. This calculator uses those figures based on the sex and age you enter.
Why do most people fall short?
US government survey data puts average adult fiber intake around 14g/day — roughly half of the typical target. Fiber isn't concentrated in any one food group, so hitting the target usually means combining several servings of whole grains, legumes, fruit, and vegetables across the day rather than one large source.
Is it safe to increase fiber quickly?
Raising fiber intake too quickly is the most common cause of bloating, gas, or cramping — not fiber itself. Increasing gradually over 1–2 weeks and drinking enough water lets your digestive system adjust.
Why isn't fiber tracking free in my nutrition app?
Several widely used nutrition apps show calories on the free tier but put fiber tracking behind a paid subscription, or bury it a few taps deep. This tool only tracks fiber, so there's nothing to unlock.
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Update history
- 2026-09-03 Fixed: the 8 food icons could fail to render on some mobile browsers (removed loading="lazy", which isn't needed for small icons already in view on load).
- 2026-09-03 Age is now a slider instead of a number field, and the sex toggle shows an icon for each option.
- 2026-09-03 Added an original illustration icon for each of the 8 foods — image recognition is faster than reading text labels.
- 2026-09-03 Launched: fiber intake calculator with an age/sex-based daily target and a running tally of today's fiber from 8 common high-fiber foods. Entirely client-side.