Vitamin D Calculator https://vitamindcalculator.net Science-based tools and guides for understanding your vitamin D needs. en Mon, 03 Aug 2026 01:42:32 GMT The Complete Guide to Vitamin D https://vitamindcalculator.net/vitamin-d-guide https://vitamindcalculator.net/vitamin-d-guide Fri, 01 May 2026 12:00:00 GMT An in-depth, science-backed guide to vitamin D covering sources, deficiency risks, blood test levels, supplementation, and vitamin D winter. How the Vitamin D Calculator Works — The Science https://vitamindcalculator.net/how-it-works https://vitamindcalculator.net/how-it-works Fri, 01 May 2026 12:00:00 GMT The physics and physiology behind our sunlight-to-vitamin-D model. Latent Vitamin D Reserves Calculator https://vitamindcalculator.net/vitamin-d-reserves https://vitamindcalculator.net/vitamin-d-reserves Fri, 01 May 2026 12:00:00 GMT Two-compartment pharmacokinetic model for stored cholecalciferol. 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