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Dilution and cap table calculator

Dilution & cap table calculator

Model ownership dilution from funding rounds and option pool expansions. Use this cap table calculator to understand post-money ownership before you sign a term sheet.

Ownership clarity

See how pre-money, investment size, and pools shift ownership.

Dilution impact

Quantify founder dilution before and after the round.

Option pool effects

Understand how expanding the pool reduces existing ownership.

Enter your round inputs

Use pre-money valuation and investment size to model ownership post-round.

Founder tip

Option pool expansions are usually priced pre-money. Confirm with your investor how the pool is set.

Ownership snapshot

See post-money ownership and dilution instantly.

Post-money valuation

$10,000,000

Investor ownership

20.0%

Founder post-money

59.5%

Option pool post-money

8.0%

Founder dilution

25.6%

Share this model

Links include your inputs so your team sees the same dilution assumptions.

How dilution is calculated

We assume the option pool is refreshed pre-money, then apply the investment to calculate post-money ownership. The founder post-money percentage reflects both pool expansion and investor dilution.

1. Pool expansion

Increase the option pool to the target percentage pre-money.

2. Investor ownership

Investor % = investment / post-money valuation.

3. Founder post-money

Founder % after pool and investor dilution.

This calculator uses simplified ownership math. Always confirm details with your cap table software.

Why cap tables matter

Dilution planning keeps founders aligned before fundraising. Understanding cap table impact helps you negotiate option pools and investment size with confidence.

Keyword tip

Founders search for "cap table calculator", "startup dilution calculator", and "option pool dilution".

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FAQs

What is dilution?

Dilution is the reduction in ownership percentage when new shares are issued to investors or option pools.

How does the option pool affect founders?

Option pool expansion usually comes out of pre-money ownership, reducing founder and existing holder percentages.

How is post-money valuation calculated?

Post-money valuation equals pre-money valuation plus the new investment amount.

Is my data stored?

No. All calculations run locally in your browser and nothing is stored on the server.