Author name: Emily Collins, Nutrition Researcher (Supplements & Superfoods)

Supplement Calculators & Tools: Dosing, Timing & Comparison Tools Free, evidence-based supplement calculators and tools — dosing, timing, unit conversions, stack builders and brand comparisons. Educational only; not medical advice. Talk to a healthcare professional before changing your regimen. Dose Calculators Apigenin Dose Calculator (Sleep, Longevity, By Goal) B12 Dose by Form Calculator (Methyl vs

Calculate elemental zinc by form. “50 mg zinc picolinate” delivers different elemental zinc than “50 mg zinc oxide.” Includes RDA, common cold protocols, and the copper-depletion warning most labels don’t disclose. Math, not medical advice. The 40 mg/day ceiling: chronic intake above 40 mg elemental zinc depletes copper over months. Most “high-dose immune” formulas at

Match your vitamin D dose to the right K2 (MK-4 or MK-7) amount based on bone-health trial ratios. Calculator also flags the magnesium cofactor that most stack labels ignore. Math + RCT references, not medical advice. Why stack D with K2: vitamin D raises calcium absorption from the gut; K2-dependent proteins (osteocalcin, MGP) direct that

Convert vitamins A, E, and K between metric units (mcg/mg) and International Units (IU). Each vitamin has its own conversion factor, and vitamin E differs by form. For vitamin D, see our dedicated D converter. Why IU vs mcg matters: The 2020 FDA Nutrition Facts label moved from IU to mcg/mg as primary, but older

Calculate spermidine dose by goal — autophagy / longevity, cognitive support, hair growth. Trial doses range from 1.2 mg (food intake) to 6 mg (supplement protocols). Wheat germ is the cheapest natural source; branded supplements offer convenience at premium price. Math, not medical advice. Honest caveat: spermidine human RCT evidence is preliminary. SmartAge trial (Schwarz

Calculate trans-resveratrol dose. Stilbene polyphenol found in red wine, grapes, Japanese knotweed (the standard supplement source). 2010s hype was excessive — early sirtuin-activation claims were oversold; David Sinclair-era enthusiasm has moderated. Real but modest CV / metabolic effects in some populations. Math, not medical advice. Honest framing: trans-resveratrol has real biological activity but effect sizes

Calculate quercetin dose by goal. Flavonoid found in onions, apples, capers. Three main use cases: allergies (mast cell stabilizer), senolytic protocols (with fisetin or dasatinib), cardiovascular / anti-inflammatory. Absorption is poor — form matters. Math, not medical advice. Bioavailability problem: standard quercetin (quercetin dihydrate) absorbs poorly — under 5% from a typical oral dose. Phytosome

Calculate a personalized pre-workout stack: caffeine + L-theanine + creatine + beta-alanine + citrulline. Each component has strong evidence individually. Scales caffeine to body weight, applies the 1:2 caffeine:theanine smoothing ratio, and warns about beta-alanine paresthesia. Math, not medical advice. Why a custom stack beats commercial pre-workout: commercial pre-workouts hide ingredient amounts in “proprietary blends”

Calculate NMN (nicotinamide mononucleotide) or NR (nicotinamide riboside) dose. Both are NAD+ precursors. NR (Niagen) has GRAS status + Chromadex commercial protection. NMN had FDA reclassification action in 2022 (status remains debated). Honest framing on longevity evidence. Math, not medical advice. Regulatory and evidence reality check: NMN was effectively reclassified by FDA in 2022 as