# How much fiber do I need?

Works out your daily dietary fiber goal from the calories you eat (14 g per 1,000 calories, Dietary Guidelines for Americans) and how far the fiber you eat is from it.

- Page: https://www.acalculator.org/health/fiber-calculator
- JSON spec: https://www.acalculator.org/health/fiber-calculator.json
- Version: 8992b8a4b0e0

## Default answer

Example with the default inputs (Calories per day 2,000): At 2,000 calories a day, aim for 28 g of fiber a day.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| cal | Calories per day | The calories you eat in a day. 2,000 is the Nutrition Facts label’s reference amount. |
| eaten | Fiber you eat (g) | The grams of fiber you eat in a day, from food labels. Leave it empty to see only the goal. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| goal | Fiber goal | 14 g of fiber for every 1,000 calories you eat, in grams per day. |
| percent | Share of the goal | The fiber you eat as a percent of the goal. |
| gap | Fiber still to add | Grams of fiber to add a day to reach the goal; 0 when you reach it. |
| status | Status | Whether the fiber you eat reaches the goal. |
| dailyValue | Share of the 28 g Daily Value | The goal as a percent of the 28 g Daily Value on Nutrition Facts labels. |

## Method

fiber goal (g) = calories × 14 ÷ 1,000; share = fiber eaten ÷ goal; still to add = goal − fiber eaten (not below 0).

## Assumptions

- The goal follows the Dietary Guidelines for Americans 2020–2025: 14 g of dietary fiber per 1,000 calories.
- It is a general goal for healthy people, not a treatment plan. People with a digestive condition should ask a doctor.
- The 28 g Daily Value on food labels is the goal for 2,000 calories.

## Worked examples

1. cal = 2,000 gives goal = 28, dailyValue = 100%. Source: NIDDK, Eating, Diet, & Nutrition for Diverticular Disease (14 grams per 1,000 calories; 28 grams for a 2,000-calorie diet). https://www.niddk.nih.gov/health-information/digestive-diseases/diverticulosis-diverticulitis/eating-diet-nutrition; U.S. Department of Agriculture and U.S. Department of Health and Human Services, Dietary Guidelines for Americans, 2020–2025, Appendix 1 (dietary fiber 14 g per 1,000 calories). https://www.dietaryguidelines.gov/sites/default/files/2021-03/Dietary_Guidelines_for_Americans-2020-2025.pdf; U.S. Food and Drug Administration, Daily Value on the Nutrition and Supplement Facts Labels (dietary fiber 28 g). https://www.fda.gov/food/nutrition-facts-label/daily-value-nutrition-and-supplement-facts-labels.
2. cal = 2,500, eaten = 20 gives goal = 35, percent = 57.142857%, gap = 15, status = Below the goal.. Source: U.S. Department of Agriculture and U.S. Department of Health and Human Services, Dietary Guidelines for Americans, 2020–2025, Appendix 1 (dietary fiber 14 g per 1,000 calories). https://www.dietaryguidelines.gov/sites/default/files/2021-03/Dietary_Guidelines_for_Americans-2020-2025.pdf.
3. cal = 1,800, eaten = 30 gives goal = 25.2, gap = 0, status = You reach the goal., percent = 119.047619%. Source: U.S. Department of Agriculture and U.S. Department of Health and Human Services, Dietary Guidelines for Americans, 2020–2025, Appendix 1 (dietary fiber 14 g per 1,000 calories). https://www.dietaryguidelines.gov/sites/default/files/2021-03/Dietary_Guidelines_for_Americans-2020-2025.pdf.

## FAQ

### How much fiber should I eat a day?

The Dietary Guidelines for Americans 2020–2025 set a goal of 14 g of fiber for every 1,000 calories you eat. At 2,000 calories that is 28 g a day; at 2,500 calories it is 35 g.

### Why does the goal depend on calories?

People who eat more food need more fiber in it. Tying the goal to calories keeps the share of fiber in the diet the same, whatever the amount of food.

### What is the Daily Value for fiber?

The Nutrition Facts label uses a Daily Value of 28 g of fiber, which is the goal for 2,000 calories. A food with 7 g of fiber gives 25% of the Daily Value.

### How do I count the fiber I eat?

Add the grams of dietary fiber on the Nutrition Facts labels of what you eat in a day, times the number of servings. Fruits, vegetables, beans and whole grains are good sources.

### Can I eat too much fiber?

Adding a lot of fiber at once can cause gas and bloating. Add it slowly over a few weeks and drink enough water. If you have a digestive condition, ask a doctor how much fiber is right for you.

### Is this goal for children too?

This page gives the general 14 g per 1,000 calories rule. The Dietary Guidelines list goals for each age group; use them with a doctor for young children.

## Sources

- U.S. Department of Agriculture and U.S. Department of Health and Human Services, Dietary Guidelines for Americans, 2020–2025, Appendix 1 (dietary fiber goal 14 g per 1,000 calories). https://www.dietaryguidelines.gov/sites/default/files/2021-03/Dietary_Guidelines_for_Americans-2020-2025.pdf (retrieved 2026-10-02)
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Eating, Diet, & Nutrition for Diverticular Disease (the Dietary Guidelines’ 14 grams per 1,000 calories; 28 grams for a 2,000-calorie diet). https://www.niddk.nih.gov/health-information/digestive-diseases/diverticulosis-diverticulitis/eating-diet-nutrition (retrieved 2026-10-02)
- U.S. Food and Drug Administration, Daily Value on the Nutrition and Supplement Facts Labels (dietary fiber 28 g). https://www.fda.gov/food/nutrition-facts-label/daily-value-nutrition-and-supplement-facts-labels (retrieved 2026-10-02)