Equity Dilution Calculator

Calculate founder equity dilution from investment rounds. Model pre/post-money valuation, multiple rounds (Seed → Series A → B), option pool top-ups, and liquidation preference waterfall.

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Post-Money Valuation
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New Investor Ownership —
Founder Ownership After —
Dilution —
Extended More scenarios, charts & detailed breakdown ▾
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Post-Money Valuation
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Founder Ownership After —
Investor Share —
Dilution —
Professional Full parameters & maximum detail ▾
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Round Economics

Post-Money Valuation —
Founder Ownership After —

Exit Waterfall

Founder Exit Value —
Investor Exit Value —
Liquidation Preference Amount —
Founder Exit After Liquidation Pref —

How to Use This Calculator

  1. Enter Current Founder Ownership %, Investment Amount, and Pre-Money Valuation.
  2. Post-money valuation, investor share, and founder dilution appear instantly.
  3. Use Multiple Rounds to model Seed → Series A → Series B dilution.
  4. Use Option Pool to add pre-money pool top-ups.
  5. Switch to Professional for exit waterfall and liquidation preference analysis.

Formula

Post-Money = Pre-Money + Investment

Investor % = Investment / Post-Money

Founder After = Founder Before × (1 − Investor %)

Example

Founder: 70%, Pre-money: $8M, Investment: $2M → Post-money: $10M, Investor: 20%, Founder after: 56%.

Frequently Asked Questions

  • Equity dilution occurs when a company issues new shares (to investors, employees, or advisors), reducing existing shareholders' ownership percentage. If you own 70% and issue 20% to new investors, you now own 70% × (1 − 20%) = 56%.
  • Pre-money valuation is the company's value before the investment. Post-money = pre-money + investment. If pre-money is $8M and you raise $2M, post-money is $10M — and the investor owns $2M / $10M = 20%.
  • An option pool is equity reserved for future employee grants (typically 10–20% of post-money). Investors usually require the pool to be created pre-money (from existing shareholders), which means founders bear the dilution before the round closes.
  • A liquidation preference guarantees investors receive their money back (often 1× the investment, sometimes 2×) before other shareholders receive anything in an exit. A 1× non-participating preference on $2M means investors get $2M first, then remaining proceeds are distributed pro-rata.
  • Seed: 10–20%. Series A: 15–25%. Series B: 10–20%. After Seed + A + B, founders typically own 40–60%. Below 30–35% cumulative founder ownership starts to affect incentives, and VCs generally prefer founders to retain meaningful equity.

Related Calculators

Sources & References (5) ▾
  1. AngelList Cap Table 101 — AngelList
  2. Cooley GO Founder Equity Guide — Cooley LLP
  3. Y Combinator SAFE Primer — Y Combinator
  4. Carta Cap Table Guide — Carta
  5. Venture Deals — Brad Feld & Jason Mendelson — Brad Feld / Foundry Group