Fiber calculator
How much fiber do I need?
Most adults fall well short of the recommended daily fiber intake. Enter a few details to see your target, based on the Institute of Medicine Adequate Intake values for total dietary fiber.
Your daily fiber target
25 g / day
Based on the Adequate Intake for total dietary fiber for a 35-year-old female.
How the recommendation works
The Adequate Intake for fiber is built on the observation that about 14 grams of fiber per 1,000 calories supports heart and digestive health. That translates into roughly 25 g/day for adult women and 38 g/day for adult men under 50, with slightly lower targets after 50 as calorie needs fall.
Increase fiber gradually and drink plenty of water - a sudden jump can cause bloating. Mix soluble and insoluble sources across legumes, vegetables, fruit, whole grains, nuts, and seeds.
Read next
Turning a target into meals
A number is the easy part. These free guides cover what to actually eat to reach it.
7 min readSoluble vs Insoluble Fiber: What Each One Actually DoesWhat soluble and insoluble fiber physically do, which foods lean which way, and why the split matters far less than the total. With grams from 961 foods.8 min readHow to Eat 30 g of Fiber a Day, Without Living on BranTwo worked 30 g days built from real foods and real USDA gram counts, the swaps that add the most, and where the grams quietly disappear.7 min readLegumes vs Whole Grains: Which Really Delivers More Fiber?Per serving, legumes carry two to four times the fiber of whole grains. Here is the gap in USDA grams, why it exists, and where grains still win.7 min readWhy Adding Fiber Causes Bloating, and How to Ramp Up ProperlyGas after a fiber increase usually comes from the size of the jump, not the fiber. A four-week ramp with real gram counts, and what makes it worse.7 min readGetting Enough Fiber on a Low-FODMAP DietA low-FODMAP elimination phase removes several of the highest-fiber foods at once. Here is the size of that gap in grams, and where the rest can come from.7 min readFiber on a Low-Carb or Keto Diet: Where the Grams Come FromCutting grains and legumes removes most of a normal fiber intake. Here is what is left, in USDA grams, and how a low-carb day still reaches 30 g.7 min read30 Plants a Week: What the Target Means and How to Count ItWhere the 30-plants-a-week idea came from, why plant variety is a different measurement from fiber grams, and a worked week that gets there.6 min readHigh-Fiber Breakfast: Five Real Options, With the GramsBreakfast is the easiest meal to fix. Five worked high-fiber breakfasts from 13 g to 22 g, the stir-in trick, and how to read a cereal box properly.