This calculator estimates investor and existing-holder ownership after a seed financing. It uses pre-money valuation, new investment, and an optional post-financing option-pool percentage to show the implied post-money capitalization.
The output is useful for evaluating term-sheet economics and dilution at a high level. It does not replace a fully diluted cap table, but it makes the relationship between valuation, check size, and reserved equity easier to see.
1. Enter the pre-money valuation
Use the negotiated company value immediately before the new investment.
2. Enter the investment amount
Provide the total new primary capital included in the financing.
3. Set the option pool
Enter the target pool as a percentage of fully diluted ownership after financing.
4. Review ownership
Compare the investor, existing-holder, and option-pool percentages.
5. Model alternatives
Change valuation, check size, or pool size to see how each term affects dilution.
Post-money valuation = Pre-money valuation + New investment
Raw investor ownership = New investment ÷ Post-money valuation
Investor ownership after pool = Raw investor ownership × (1 − Option pool %)
Existing-holder ownership = (1 − Raw investor ownership) × (1 − Option pool %)
The model treats the option pool as a post-financing ownership slice. Actual term sheets may place pool expansion pre-money, changing who bears the dilution.
The main result is the estimated investor share after reserving the entered post-financing option pool.
SAFEs, notes, secondary sales, warrants, and existing options require a detailed cap table.
Given: $8 million pre-money valuation, $2 million investment, and a 10% post-financing option pool.
Calculation: Post-money valuation = $10 million. Raw investor ownership = $2 million ÷ $10 million = 20%. After the pool, investor ownership = 20% × 90% = 18%. Existing holders retain 80% × 90% = 72%, and the pool is 10%.
Result: Investor 18%, existing holders 72%, option pool 10%.
This model treats the pool as a new post-financing ownership slice that dilutes both investor and existing holders proportionally.
Existing holders usually bear more of the dilution. A detailed cap-table model is needed to reflect that structure accurately.
Use only primary capital for this ownership formula. Secondary purchases transfer ownership but do not increase company cash or post-money valuation in the same way.
Not in this simplified input set. Converted instruments can materially change fully diluted ownership and should be modeled separately.
Ownership is the percentage held after the transaction. Dilution is the decrease in an existing holder’s percentage caused by new securities or pools.