Equity Dilution Calculator

See exactly how a funding round dilutes your ownership. Enter your current stake, the pre-money valuation, and the new investment — get your post-round percentage, the points you give up, and what your slice is worth. Everything runs in your browser; nothing is uploaded.

📖 How it works & FAQ

Your current ownership (%)

Pre-money valuation ($)

New investment ($)

How a funding round dilutes your ownership

When a company raises money, it doesn't sell existing shares — it issues new ones to the investors. The pie gets bigger, so every existing slice becomes a smaller percentage of the whole. The math is simple: post-money valuation = pre-money valuation + new investment, and your new ownership = your old percentage × (pre-money ÷ post-money). If you own 25% before a $2M raise at an $8M pre-money, you own 25% × 8/10 = 20% after.

Here's the part founders often miss: at a fair valuation, dilution doesn't make you poorer on paper. Your 20% of a $10M company is worth exactly what your 25% of the $8M company was — $2M either way. You hold a smaller slice of a bigger, better-funded pie. Dilution hurts when the round is priced low, when option pools are carved out of your side, or when the new capital doesn't grow the company.

Results are estimates only, not professional, financial, tax, or legal advice; real term sheets include option pools, preferences, and other terms that change the outcome.

How to use it

Enter your current ownership percentage — your fully diluted stake before the round.
Enter the pre-money valuation the investors have agreed to.
Enter the total new investment coming in. Results update live: your new percentage, points lost, implied stake value, and the investors' share.

FAQ

Does everyone get diluted equally?: In a plain priced round, yes — every existing holder's percentage is multiplied by the same pre/post ratio. Pro-rata rights let investors buy more shares to maintain their percentage.
What about the option pool?: Investors often require an expanded employee option pool created before the round, which comes out of existing holders. That adds dilution beyond what this calculator shows — model it as extra "investment" at zero dollars or lower your starting percentage.
Is dilution bad?: Not inherently. Owning 20% of a company that succeeds beats 100% of one that runs out of cash. Judge the round by the price and what the capital buys.
Is my data uploaded anywhere?: No. Everything runs in your browser; nothing is sent to a server.