Startup Cap Table Calculator & Simulator
A cap table is the single source of truth for who owns what — and the first thing investors and acquirers ask for. This simulator builds yours from founder shares up, then layers on each funding round so you can see exactly how pre-money valuations, option pools and new investors reshape ownership over time. Model your seed, Series A and beyond, and watch your founder stake evolve round by round.
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Methodology
How it works
How the cap table is calculated
Everything is modelled in shares, because that's the only honest way to compound dilution across several rounds. Founders start with a share count; each round prices new shares off the pre-money valuation — the price per share is the pre-money divided by the existing fully-diluted shares. The new investor receives shares equal to their cheque divided by that price, which works out to investment ÷ post-money of the company.
Because new shares are issued rather than taken from anyone, every existing holder keeps their exact share count but owns a smaller slice of a larger pie. Tracking real shares (not just percentages) is what lets the model stay correct after two, three or four rounds — percentages alone drift.
The option pool shuffle — who really pays
Investors almost always require an employee option pool to be created or topped up as part of a round, and they want it counted in the pre-money. That means the pool is carved out of the existing shareholders' equity — the founders — not the incoming investor. This simulator models pool top-ups the standard pre-money way, so a 10% post-round pool costs founders several extra points on top of the investor's stake.
If an existing pool is already larger than the target, it isn't shrunk — it simply dilutes alongside everyone else. Negotiating pool size, and whether it sits in the pre- or post-money, is one of the highest-leverage terms in any early round.
Why founder ownership compounds downward
Each round multiplies your ownership by roughly (1 − the new investor's percentage), so dilution stacks. Selling 20% at seed and another 20% at Series A doesn't leave you with 60% — it leaves you closer to 64% of what you had, before any option pools. The ownership-over-time view makes this visible: you can watch the founders' slice shrink while the price per share (hopefully) climbs.
A rising share price is the whole point — owning a smaller percentage of a far more valuable company is how founders build real wealth. The goal isn't to avoid dilution, it's to take it deliberately.
Use it to plan your raise
Model the rounds you expect, then sanity-check the end state: do the founders retain enough ownership and motivation by the time you reach Series B? Is the pool big enough to hire without a painful top-up next round? Adjust pre-money, cheque size and pool until the trajectory looks healthy, then use it to pressure-test any term sheet you're handed.
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