Startup Equity Dilution Calculator
See how much of your company you actually keep after a sequence of funding rounds. Set your starting stake, then add each round's raise, pre-money valuation and option pool to watch your ownership dilute over time.
Your stake
Funding rounds
Each round issues new shares, so your percentage shrinks. Add the raise, the pre-money valuation and any new option pool (carved pre-money).
Round-by-round dilution
| Round | Raise | Post-money | Round dilution | Your % after | Your value |
|---|
How equity dilution works across rounds
Every priced round issues new shares. Your share count doesn't change, but the total grows, so your percentage falls. For a single round the new investor takes raise ÷ post-money (post-money = pre-money + raise). A new option pool is usually carved pre-money, which dilutes existing shareholders — including you — on top of the investor's stake.
Across several rounds, dilution compounds. If you keep 80% through a round and 85% through the next, you're left with 0.80 × 0.85 = 68% of what you started with. This calculator applies each round in order and multiplies the effect, so the final number reflects the full Seed → Series A → B → … path, not just one round.
Founders commonly end up with a 10–20% stake by the time a company is several rounds in. To protect ownership, focus on round size, valuation and how large a pool each investor asks you to create. For the full per-shareholder breakdown of a single round, use the cap table calculator; to plan the raises themselves, see the SaaS fundraising guide. This tool is a fast estimate, not legal or investment advice.
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Model dilution against runway and hiring
Adlega ties your ownership to the actual financial plan — so you can see how each raise affects dilution, runway and the milestones it has to buy.