Fully Diluted Valuation (FDV) answers a different question than everyday market cap: not "what is this coin worth right now," but "what would it be worth if every token that will ever exist were already trading." It is calculated by multiplying the current price by the maximum supply (or total supply, for assets without a hard cap), rather than the smaller circulating supply used for standard market cap.
For an established asset like Bitcoin, where nearly all of the 21 million coin cap is already mined, FDV sits close to market cap. The gap becomes meaningful for newer tokens, where a large share of the total supply is still locked in team allocations, investor vesting schedules, staking rewards, or ecosystem funds not yet released to the market.
Traders watch the ratio between FDV and market cap as a rough dilution gauge. A token trading at a small fraction of its FDV signals that a large amount of future supply could eventually reach the market, potentially pressuring price as vesting cliffs and unlock events arrive. This pattern, often called "low float, high FDV," became a widely discussed risk during 2024-2026 token launches, where projects listed with only a small circulating share against a headline valuation implying the entire, much larger future supply.
FDV is a useful comparison tool but not a price target: it assumes constant demand as supply grows, which rarely holds, and it can be distorted for tokens with unusual mint or burn mechanics.