Riboflavin Intake Calculator
Score daily vitamin B2 percent and gap from foods by stage.
What it does
Riboflavin keeps energy metabolism turning. Dairy, eggs, and fortified grains carry it, and light exposure quietly destroys it in stored milk.
The tool above scores the day. An adult woman target is 1.1 mg, so 0.9 mg reads 81.8 % with 0.2 mg more to find. Men target 1.3 mg, breastfeeding 1.6 mg.
Dairy leads most scores. A glass of milk with fortified cereal covers half the day before lunch, while eggs and almonds fill afternoons.
Light is the quiet thief. Milk in clear jugs under bright cases loses B2 faster than cartons, so storage matters as much as shopping.
Weeks beat days. Travel and skipped breakfasts swing any single tally, so average seven before acting.
How to use
- Pick life stage.
- Enter food riboflavin in mg.
- Read target first.
- Read percent next.
- Read gap and add dairy or eggs.
- Score a week, not one meal.
Formula
- stage
- Life stage setting the target.
- food
- Riboflavin from foods, in mg.
Targets follow NIH ODS recommended intakes. Food mg comes from labels or USDA FoodData entries summed for the day.
Worked example
Example: adult woman, 0.9 mg from food
Defaults: adult woman eating 0.9 mg. These are also the default values, so the page opens on this answer.
- Stage: adult woman, target 1.1 mg.
- Food: 0.9 mg from dairy and grains.
- Share: 0.9 / 1.1 x 100 = 81.8 %.
- Gap: 1.1 - 0.9 = 0.2 mg more.
- Tool shows 1.1 mg, 81.8 %, 0.2 mg more.
Reference table
| Stage | Target | Example score |
|---|---|---|
| Child | 0.6 mg | 0.4 mg is 66.7 % |
| Teen girl | 1.0 mg | 0.8 mg is 80 % |
| Adult woman | 1.1 mg | 0.9 mg is 81.8 % |
| Adult man | 1.3 mg | 1.0 mg is 76.9 % |
Limits
- Intake scoring only, not medical advice.
- Labels vary by brand and fortification.
- Light losses shift real intake.
- Symptoms need clinicians, not math.
Common mistakes
- Scoring one snack instead of the day.
- Mixing mcg and mg on labels.
- Clear jug milk under bright light.
- Skipping dairy with no backup plan.
- Treating percent as a diagnosis.
Try it yourself
Quick checks. Answers sit tucked under each question.
Adult man eating 1.0 mg?
Target is 1.3 mg. Share is 1.0 / 1.3 x 100 = 76.9 %. Gap is 0.3 mg more.
Child eating 0.4 mg?
Target is 0.6 mg. Share is 0.4 / 0.6 x 100 = 66.7 %. Gap is 0.2 mg more.
Questions
How do I score my day?
Divide food mg by the stage target. Here 0.9 / 1.1 x 100 = 81.8 %.
What are the targets?
Kids 0.6 mg, teen girls 1.0 mg, teen boys and men 1.3 mg, women 1.1 mg, pregnancy 1.4 mg, breastfeeding 1.6 mg.
Which foods carry riboflavin?
Milk, yogurt, eggs, almonds, and fortified cereals. A glass of milk plus cereal covers half the day.
How do I close the gap?
Add dairy, eggs, or almonds. Here 0.2 mg more closes the day.
Does light matter?
Yes. Light destroys B2, so milk in clear jugs on lit shelves loses more than cartons.
Does this diagnose deficiency?
No. Intake scoring only; cracked lips and sore tongue need clinicians.