See how much existing ownership is diluted by a new round, including any new option pool.
Dilution is multiplicative, not additive: your stake is scaled down by whatever share of the company new investors and the option pool take. Value can still rise even as ownership falls, provided the valuation rises by more than the dilution. Founders track percentage points but investors track value — comparing the before and after stake values is what shows whether a round was worth the dilution.
Dilution
Ownership after = current ownership × (100% − investor share − new option pool)
Ownership after = current ownership × (100% − investor share − new option pool) Dilution is multiplicative, not additive: your stake is scaled down by whatever share of the company new investors and the option pool take. Value can still rise even as ownership falls, provided the valuation rises by more than the dilution.
Founders track percentage points but investors track value — comparing the before and after stake values is what shows whether a round was worth the dilution.
This calculator takes 4 inputs: Your current ownership, Pre-money valuation, New investment, New option pool created. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.