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Dilution Calculator
Calculate how much your ownership percentage drops when new shares are issued, from your existing share count and the number of new shares.
How to Use Dilution Calculator
- 1Enter your existing share count
- 2Enter the number of new shares being issued
- 3Click Calculate to see your ownership percentage before and after
Frequently Asked Questions
Total Shares After = Existing Shares + New Shares Issued. Your New Ownership % = Existing Shares ÷ Total Shares After × 100 — down from 100% before the new shares existed.
Not necessarily — your ownership PERCENTAGE drops, but if the new investment increases the company's total value by more than your percentage drops, your shares' dollar value can still rise. This tool only computes the percentage change, not value impact.
It depends on the round's structure (price per share and investment amount, or a target post-money ownership %) — if you know the investment amount and price per share, new shares = investment ÷ price per share.
No — enter the option pool shares as part of "new shares issued" if a pool is being created in the same round, since it dilutes existing holders the same way.
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