What is calculated
Oral vitamin D from entered food and supplements.
Vitamin D Intake Calculator
Entered vitamin D intake
Enter your values, then calculate to see a verified result.
Reference range
How this result is calculated
A clear calculation path based on your inputs.
Inputs usedReview the information used for this result.
Full calculation and sourcesOpen Full calculation and sources to review the formula, assumptions, boundaries, and evidence.
Versioned calculationFormula v1.0.1
Method
Add like-for-like amounts and convert mcg to IU.
Important boundary
Sun exposure, absorption, blood 25(OH)D, disease, and treatment are not calculated.
Read both labelsUse the labeled input and matching unit.
Measured or label valueNormalize mcg and IUThe calculator applies the stated equation.
Full precision firstKeep blood status separateKeep the boundary beside the result.
Reference, not diagnosisInterpretation
mcg/day is the entered oral total.
IU and reference percentages remain visible.
A blood test or clinician-directed treatment cannot be replaced by this total.
Use this result
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Related calculators and resources
OSTA Osteoporosis Screening CalculatorApply the source-specific age-and-weight screen.Metabolic Syndrome Criteria CheckerAudit all five NHLBI criteria.Supplement Stack CalculatorAudit duplicate amounts of one ingredient across products.Magnesium Intake CalculatorKeep another nutrient audit separate.
Method and test recordFormula v1.0.1
- Recorded scope
- health-wellness-completion
- Publisher
- CalculatorGeek
- Recorded review date
- 2026-10-05
- Next source review
- 2027-04-05
- Definition fixtures
- 2 configured scenarios
- Published examples
- 2 shown below
Recorded method
Verify mcg/IU conversion, age reference switching, totals, and upper-limit comparison.
These records describe the published model and reference tests. A test-case count is not a certification of every possible input or an independent specialist review. Editorial policy
Known limitations
- Does not estimate vitamin D made from sunlight.
- Does not infer blood 25(OH)D.
- Not for pediatric, pregnancy, deficiency-treatment, or disease-specific dosing.
- Reference percentages are not personal prescriptions.
Method sources
Latest model update
2026-10-05 - Initial evidence-limited shared-system implementation with fixtures, original support content, and contextual links.
Reference inputs and expected results
Up to 12 examples from the configured definition fixtures are shown. Expected values use the stated output units; invalid inputs are intended to be rejected.
| Case | Inputs | Expected result |
|---|---|---|
| adult six hundred IU total | Vitamin D from food and beverages: 5 mcg; Vitamin D from supplements: 10 mcg; Adult age reference: adult | Entered vitamin D intake: 15 mcg/day; Equivalent international units: 600 IU/day; rda: 15; Share of selected NIH RDA: 100 %; Share of adult NIH upper limit: 15 % (allowed numeric tolerance: 0.0001) |
| IU input equivalence | Vitamin D from food and beverages: 200 IU; Vitamin D from supplements: 400 IU; Adult age reference: adult | Entered vitamin D intake: 15 mcg/day; Equivalent international units: 600 IU/day (allowed numeric tolerance: 0.0001) |
Report an issue with this tool. Include the page URL, units, expected answer, and steps to reproduce. Do not include sensitive personal information.
On this page
What the Vitamin D Intake Calculator calculates
Add oral vitamin D from food and supplements and compare the total with cited adult NIH reference values.
The tool is an intake audit, not a dose recommendation or vitamin D status calculator.
Continue this workflow with the OSTA Osteoporosis Screening Calculator. Apply the source-specific age-and-weight screen.
How to use the Vitamin D Intake Calculator
- Enter food and beverage vitamin D.
- Enter supplement vitamin D.
- Choose the adult age reference.
- Keep prescribed treatment and laboratory interpretation outside the result.
Continue with the Supplement Stack Calculator. Audit duplicate amounts of one ingredient across products.
Formula, variables and calculation order
total mcg = food mcg + supplement mcg; IU = mcg x 40.
Inputs are validated and normalized before calculation. Full precision is retained until the displayed result is rounded.
Cross-check a different part of the decision with the Magnesium Intake Calculator. Keep another nutrient audit separate.
Worked example and boundary check
Worked example
5 mcg from food plus 10 mcg from supplements equals 15 mcg or 600 IU.
Boundary check
The adult upper limit is not a treatment target, and clinicians may supervise different doses for specific conditions.
How to interpret the result
Use the result to reconcile labels. Blood status, deficiency treatment, pregnancy, kidney disease, and malabsorption need appropriate care.
- Does not estimate vitamin D made from sunlight.
- Does not infer blood 25(OH)D.
- Not for pediatric, pregnancy, deficiency-treatment, or disease-specific dosing.
- Reference percentages are not personal prescriptions.
For a separate result with different assumptions, open the Calorie Calculator. Keep energy planning separate from micronutrient status.
Frequently asked questions
Is 100 mcg a target?
No. It is the adult tolerable upper intake level, not a goal.
Can I enter IU?
Yes; the unit converter uses 40 IU per mcg.
Does this tell me if I am deficient?
No.
What about a prescribed high dose?
Follow the prescriber and do not use this audit to replace that plan.
Primary sources and evidence limits
Sources were checked 2026-10-05. A reference value, conversion, or schedule estimate is not a diagnosis, prescription, individualized treatment target, or substitute for professional care.