See exactly how your ownership changes across every funding round. Add founders, model rounds, and share with cofounders.
Dilution happens because a funding round issues new shares to investors rather than transferring existing ones, so every current shareholder owns a smaller slice of a larger pie. After a priced round your ownership is:
Your ownership after the round = your shares ÷ (your shares + new shares issued)
The new shares are set by the round's terms:
Repeat this for each round (pre-seed through Series C) and the optional employee option pool to model cumulative dilution in the calculator below.
See how each stakeholder's equity evolves after every round.
Full breakdown of ownership, shares, and valuations at each stage.
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Quick reference formulas for dilution, vesting, SAFE notes, runway, and LTV:CAC. Print it out and keep it on your desk.
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Quick answers to the most common dilution questions.
Typically 15–25% per round. A seed or Series A round usually sells 15–25% of the company, so every founder's stake shrinks by roughly that fraction. Across pre-seed, seed, A, B, and C, the founding team often ends up holding 10–25% combined by exit.
Yes. A new option pool is usually created or topped up as part of a priced round. If the pool is created before the investment closes, the founders absorb that dilution rather than the incoming investors. This calculator lets you add an option pool to see the exact effect.
Pre-money is what the company is worth before the new cash; post-money is pre-money plus the investment. The investor's ownership equals investment ÷ post-money — so a $1M investment at a $4M pre-money valuation ($5M post-money) buys 20%.
No. Every calculation runs entirely in your browser. Nothing about your cap table is uploaded to a server or stored anywhere.
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