Calculator
Equity Calculator
Calculate ownership, dilution, and exit values for startup investments
Assumptions
Simplified model: This calculator uses basic dilution math without:
- -Liquidation preferences or participating rights
- -Pro-rata participation rights
- -Option pool refresh beyond specified expansions
- -Tax implications or transaction fees
- -Convertible notes or SAFE conversions
Sanity check: A $10k investment should typically yield ~$100k at 10x exit when ignoring future dilution.
Enter your investment details
Results will appear here once you calculate
How the equity calculator works
This startup equity calculator shows how many shares an investment buys, what percentage of the company that is, and what the stake is worth at a given exit.
The formulas
Shares purchased = investment / share price. Total shares = post-money valuation / share price. Ownership = shares purchased / total shares, which is the same as investment / post-money valuation.
Stake value at exit = ownership x (post-money valuation x exit multiple). This assumes no further dilution. To include dilution from later rounds, use the exit calculator.
Worked example
A $1,000 investment at $9.50 per share buys about 105 shares. At a $600M post-money valuation that is roughly 0.00017% of the company.
If the company exits at 10x that valuation ($6B), the stake is worth $10,000.
Common questions
- How do I calculate my ownership percentage in a startup?
- Divide your investment by the post-money valuation of the round. $25,000 into a $10M post-money round is 0.25%.
- What is post-money valuation?
- The value of the company right after the round, including the new money. Pre-money valuation plus the amount raised equals post-money valuation.