Do the math

A bottle price is only the beginning. The denominator matters: servings, capsules, grams of a named ingredient and usable supply answer different questions. Our examples use invented shopping inputs explicitly labeled illustrative; they are not observed market prices or quotes. Use your own checkout total and the exact package label in the calculators. Work through a single bottle before adding subscriptions or bulk purchases, and keep a separate record of cash paid and the value of what you actually use. A lower cost does not establish that a supplement is appropriate for you.

The overview introduces the common worksheet, and the individual guides work through checkout allocation, coupons, refill schedules, bulk thresholds, unused servings and inventory. Follow whichever decision is actually in front of you rather than applying every calculation to every product. Keep a copy of the original inputs so you can see whether a later difference came from the package, its formulation, a temporary offer or a changed assumption about use.