Equity Dilution Calculator – Investor Funding Round Dilution

Calculate founder ownership retention and equity dilution with our free Equity Dilution Calculator. Model post-money valuations, investor ownership stakes, option pool dilution, and post-round equity value.

Equity Dilution Calculator – Investor Funding Round Dilution
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Post-Money Valuation
Investor Ownership
New Founder Equity
Founder Ownership Drop
Post-Round Founder Equity Value
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History — Equity Dilution Calculator – Investor Funding Round Dilution

# Time Pre-Money ($) Investment ($) Investor Equity (%) Post-Round Founder Equity (%) Action

Understanding Startup Equity Dilution

When raising venture capital, startups issue new shares to investors rather than selling existing founder shares. Issuing new shares increases total shares outstanding, which dilutes existing shareholders’ percentage ownership.

Key terms: - Pre-Money Valuation: Valuation agreed upon before receiving investment ($V_{pre}$). - Investment Amount: Amount of cash raised ($I$). - Post-Money Valuation: $V_{post} = V_{pre} + I$. - Investor Ownership %: $O_{investor} = \frac{I}{V_{post}} \times 100$.


Equity Dilution Mathematical Formulas

\[\text{Post-Money Valuation} = V_{pre} + I\] \[\text{Investor Ownership (\%)} = \left( \frac{I}{V_{post}} \right) \times 100\] \[\text{New Founder Ownership (\%)} = O_{founder, pre} \times \left( 1 - \frac{O_{investor} + O_{pool}}{100} \right)\] \[\text{Post-Round Founder Stake Value (\$)} = V_{post} \times \left( \frac{\text{New Founder Ownership}}{100} \right)\]

Round Ownership Dilution Example

Stage / Component Pre-Round Stake Post-Round Stake Valuation Impact
Founders 80.0% 57.6% Value increases from $8.0M to $7.2M (with 10% Pool)
New Investors 0.0% 20.0% $2.5M invested at $12.5M Post
Option Pool 0.0% 10.0% Pre-money pool shuffle
Existing Investors 20.0% 12.4% Pro-rata dilution absorbed

Step-by-Step Guide to Calculating Equity Dilution

  1. Enter Pre-Money Valuation: Input the negotiated valuation before new capital.
  2. Enter Investment Amount: Input the total amount of fresh capital raised.
  3. Enter Founder Ownership %: Provide current pre-round ownership percentage.
  4. Set Option Pool Target %: Specify required unallocated option pool size.
  5. Review Post-Round Cap Table: Inspect new ownership percentages and dollar values.

Frequently Asked Questions

What is equity dilution in a startup?

Equity dilution occurs when a company issues new shares to new investors or employee option pools, reducing the ownership percentage of existing shareholders.

How is post-money valuation calculated?

Post-Money Valuation = Pre-Money Valuation + New Investment Amount.

How does an unallocated option pool cause extra dilution?

Creating an unallocated option pool pre-money forces existing founders to absorb 100% of the pool dilution before new investor capital enters.

Does dilution reduce the total dollar value of founder shares?

Not necessarily. Although founder percentage ownership decreases, if the valuation increases sufficiently, the dollar value of the founder’s stake increases.

What is a typical investor dilution percentage per round?

Priced Seed and Series A funding rounds typically dilute existing shareholders by 15% to 25% per round.

Is my cap table data secure?

Yes. All computations execute locally in your web browser with zero server data storage.