Startup dilution calculator
See exactly how a funding round changes your ownership percentage and what your stake is worth afterwards.
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Dilution
What it measures
Calculates how much your slice of the pie shrinks when you sell a new slice to investors.
When to use it
Use it when planning a fundraise, for example: if I raise $2M at $8M pre-money, what happens to my 40% stake?
Watch out for
Dilution is not always bad. Owning 10% of a $1B company is worth more than owning 100% of a company worth nothing.
Dilution
Your ownership after a funding round.
How it works
New Investor % = Amount Raised / Post-Money · Your New % = Old % × (1 − New Investor %)A funding round doesn't take shares away from anyone; it mints new ones. The company issues fresh shares to the investor, the total share count rises, and every existing holder's slice of the bigger pie shrinks proportionally. The investor's stake equals the money in divided by the post-money valuation, and everyone else is diluted by exactly that factor. The question that matters isn't whether you were diluted, but whether the capital made the whole pie grow faster than your slice shrank.
Worked example
You own 40% and the company raises €2M at an €8M pre-money valuation. Post-money is €10M, so the new investor owns 20%, and your 40% becomes 40% × 0.8 = 32%. But your 32% of a €10M company is worth €3.2M against €3.2M before the round. Dilution cost you nothing today, and if the €2M doubles the company's value, your smaller slice is worth far more. Run the next round too: dilution compounds, which is why founders typically land at 30-50% combined after Series B.
Common questions
How does dilution work in a funding round?
New shares are issued to investors, so existing holders own a smaller percentage of a bigger company. Raising €2M at €8M pre-money creates 20% new ownership, diluting everyone else proportionally.
How much equity do founders give up per round?
Typical rounds sell 15-25% of the company. After a seed and Series A-B, founders commonly hold 30-50% combined, which is why modeling dilution before you raise matters.
Is dilution always bad for founders?
No. Owning 10% of a company worth €1B beats owning 100% of one worth nothing. Dilution is the price of fuel; the question is whether the capital grows the pie faster than it shrinks your slice.
Last reviewed July 2026