Free supplement tools
17 quick, private calculators and checkers that run in your browser. Nothing you enter is stored or sent anywhere.
Supplement Finder Quiz
Answer 5 quick questions about your goals and diet and get a shortlist of evidence-backed supplements to research.
Open toolSupplement Interaction Checker
Pick the supplements you take and see which combinations compete for absorption or need extra caution.
Open toolSupplement–Drug Interaction Lookup
Choose a prescription medicine and see which supplements interact with it, and how serious it is.
Open toolVitamin D Sunlight Calculator
Enter your latitude, month and skin type to see whether sunlight can realistically make vitamin D where you live.
Open toolSupplement Evidence Database
Search popular supplements and see each claimed use graded from A (strong) to D (no good evidence).
Open toolSupplement Snake Oil Detector
Paste any supplement's marketing copy and get a red-flag score based on regulator warning signs.
Open toolNutrient Deficiency Risk Check
Tick your diet, age and medication risk factors to see which nutrients are worth asking your doctor to test.
Open toolSupplement Stack Builder
Choose the supplements you take and get a morning, meal and bedtime schedule with spacing warnings.
Open toolSupplement Label Decoder
Paste a Supplement Facts panel to see evidence grades per ingredient, upper-limit warnings and blend red flags.
Open toolSupplement Spending Audit
List what you take and what it costs to see your yearly spend, duplicated ingredients and low-evidence products.
Open toolSupplement Onset Timeline
See how long common supplements typically take to show an effect, from minutes to months.
Open toolSupplement Expiry & Storage Checker
Enter the expiry date and storage conditions to see time left and how to keep your supplements effective.
Open toolSupplement Dose Calculator
See the official daily target and upper limit for common nutrients, adjusted for your age and sex.
Open toolCost-Per-Dose Calculator
Compare two products by the real cost of the active ingredient you actually get each day.
Open toolSupplement Cost-Per-Day Calculator
Find the real daily, monthly and yearly cost of any supplement from its price and serving size.
Open toolType 2 Diabetes Risk Score
Answer 7 questions adapted from the American Diabetes Association risk test to see your type 2 diabetes risk.
Open toolCreatine Dose Calculator
Enter your body weight to get a maintenance dose and an optional loading plan.
Open tool