An estimate of a stock's intrinsic worth based on its fundamentals, regardless of its current market price.
Fair value is an estimate of a stock's "true" worth based on fundamentals — earnings, cash flows, assets, growth — rather than its momentary market price. The idea is that market price swings above and below fair value on sentiment and news. When price sits below fair value by a sufficient margin, the stock is "undervalued" and may be an opportunity; the reverse is "overvalued." Estimation methods vary (discounted cash flow, sector multiples) and all rely on assumptions, so they are estimates. FoudaLens shows a fair-value estimate per stock as a guide, not a recommendation.