Cap Table Dilution Calculator

Background.

A reader arrives at Cap Table Dilution Calculator to show the ownership created by a priced equity investment and the share count issued. A priced round sets price per share from pre-money value and existing fully diluted shares, then measures ownership against post-money capitalization. For that reason, this page names its convention as “new investor ownership = investment / post-money valuation; new shares = investment / pre-money share price.”

The editable entries are pre-money valuation, new primary investment, pre-financing fully diluted shares. Use values from the document or measurement that governs this cap table dilution question; the defaults are only the worked fixture below. Before relying on the number, check this cap table dilution boundary: option-pool increases, convertibles, warrants and transaction fees must be placed in the negotiated capitalization definition.

National Venture Capital Association, Model Legal Documents; preferred-stock financing terms documents the convention or governing rule used here. The cap table dilution output is a transparent scenario under those facts: it does not manufacture an unentered market price, professional determination, carrier quote, legal eligibility finding or locally adopted code value.

What is cap table dilution calculator?

Cap Table Dilution is the relationship behind this decision: a priced round sets price per share from pre-money value and existing fully diluted shares, then measures ownership against post-money capitalization. On this page it means new investor ownership = investment / post-money valuation; new shares = investment / pre-money share price. Option-pool increases, convertibles, warrants and transaction fees must be placed in the negotiated capitalization definition; that is the line between the reported quantity and a broader corporate finance analysis.

How to use this calculator.

1. 01Confirm that “new investor ownership = investment / post-money valuation; new shares = investment / pre-money share price” matches the cap table dilution convention you need.
2. 02Replace the fixture values for pre-money valuation, new primary investment, pre-financing fully diluted shares with dated values from the governing record.
3. 03Keep all currencies, measurement units and time periods on the same basis before calculating.
4. 04Read new investor post-money ownership together with this boundary: Option-pool increases, convertibles, warrants and transaction fees must be placed in the negotiated capitalization definition.

The formula.

The calculation uses new investor ownership = investment / post-money valuation; new shares = investment / pre-money share price. In this cap table dilution model, the entered terms are pre-money valuation, new primary investment, pre-financing fully diluted shares. A priced round sets price per share from pre-money value and existing fully diluted shares, then measures ownership against post-money capitalization, which is why the relationship is presented under this name rather than as a universal alternative. Option-pool increases, convertibles, warrants and transaction fees must be placed in the negotiated capitalization definition. Calculations keep full decimal precision through the relationship and round only the returned display values.

A worked example.

Frequently asked questions.

References& sources.

1. [1]National Venture Capital Association, Model Legal Documents; preferred-stock financing terms. Retrieved 2026-08-07. access: open unless marked otherwise.
2. [2]U.S. Securities and Exchange Commission. Investor.gov glossary: Dilution. Retrieved 2026-08-07. independence: primary; access: open.
3. [3]U.S. Securities and Exchange Commission. Investor.gov glossary: Preferred stock. Retrieved 2026-08-07. independence: primary; access: open.
4. [4]U.S. Securities and Exchange Commission. Investor.gov glossary: Stock option. Retrieved 2026-08-07. independence: primary; access: open.
5. [5]Financial Accounting Standards Board. Accounting Standards Codification. Retrieved 2026-08-07. independence: primary; access: open.