Labdoor is an independent company in San Francisco, California, that tests supplements, grade and rank products, write reports, and publish that information for free, so consumers can confidently buy the best supplements for their health.

We buy products off retail shelves and online sites. Then, we send a sample of each product to an FDA-registered laboratory for a detailed chemical analysis, which includes measurements of active ingredients and potential contaminants. 

Quality scores are comprised of individual scores for Label Accuracy, Product Purity, Nutritional Value, Ingredient Safety, and Projected Efficacy.