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Dilution Calculator
Calculate exact ownership compression after factoring in new investor equity and option pool expansions.
Inputs
New Ownership Stake
Total Dilution:
The Math
The Math: Dilution is multiplicative, not subtractive.
New % = Old % × (1 - Total % Issued in New Round)
If you own 50% and sell 20%, you don't own 30%. You own 50% of the remaining 80%, which is 40%.
Always remember that expanding the employee option pool acts exactly like selling shares to investors from a dilution perspective.