Cap Table & Dilution Calculator
Free tool · by Daniel HaketSee exactly how much of your company you'll own after raising. Enter your funding rounds (investment + pre-money) and this shows the ownership split and how founders dilute round by round — the cap-table math founders usually run in Carta or pay a lawyer for.
Founders start owning 100%. Add the funding rounds below to see how everyone gets diluted.
What this free tool is great for: a quick, one-off job with no signup — it runs entirely in your browser, so nothing leaves your device and there's nothing to manage.
Its honest limit: it's a one-off calculation in your browser — it doesn't save your scenarios, update as your real numbers change, or connect to your live accounts, so you re-enter the figures every time and can't watch how they move.
What a cap table really is
A capitalisation table is the definitive record of who owns your company and how much. In its simplest form it lists every shareholder and their slice of the pie; in a growing startup it also tracks option pools, convertible instruments and the way each funding round reshuffles everyone's percentage. It sounds like paperwork, but it's the document that determines who controls decisions, who gets what in an exit, and how much of your own company you'll still own by the time it's worth something. Getting comfortable reading a cap table — and modelling what a raise does to it — is a core founder skill, not an accountant's afterthought.
Ownership, dilution and the shrinking slice
The concept that trips people up is dilution. When you raise money by issuing new shares, the total number of shares grows, so your existing shares represent a smaller percentage of the whole. Your slice shrinks — but the pie is meant to be getting bigger, so a smaller slice of a much larger company can be worth far more. That's the whole bet of venture funding: trade ownership percentage for the capital to grow the total value faster than you dilute. Dilution isn't inherently bad; uncontrolled or poorly-priced dilution is. The point of modelling it is to make sure each slice you sell buys enough growth to justify itself.
Pre-money, post-money and price per share
Two terms decide how much you give up in a round. The pre-money valuation is what your company is deemed worth before the new money goes in; the post-money is pre-money plus the investment. The investor's ownership is simply their cheque divided by the post-money. This is why negotiating a higher pre-money matters so much: at a higher pre-money, the same investment buys the investor a smaller percentage, so you sell less of your company for the same cash. A founder who understands this arithmetic negotiates valuation with clear eyes, rather than fixating on the headline amount raised while quietly handing over more equity than they realise.
The option pool and how it quietly dilutes founders
To hire great early employees you need equity to offer them, so investors typically require you to set aside an option pool — a chunk of shares reserved for future hires. The catch that surprises first-time founders is timing: the pool is usually carved out of the pre-money, meaning it dilutes the existing shareholders (you) before the new investor comes in, not everyone equally afterwards. A larger pool demanded at the term sheet stage is effectively a lower valuation in disguise. It's not a reason to skimp — you need the pool to hire — but it is a line item to negotiate consciously rather than wave through.
SAFEs, convertible notes and deferred dilution
Early rounds often use SAFEs or convertible notes rather than priced equity. These let you raise quickly without setting a valuation today; instead the money converts into shares at your next priced round, usually with a discount or a valuation cap as a reward for the early risk. The convenience hides a trap: because the dilution happens later, at conversion, it's easy to lose track of how much of the company you've effectively already sold. Stack several SAFEs with generous caps and you can arrive at your priced round far more diluted than you expected. Modelling conversions before you sign, not after, is how founders avoid that nasty surprise.
Founder splits and the case for vesting
How co-founders divide equity at the start, and whether that equity vests, shapes everything downstream. An even split feels fair but should reflect contribution, role and risk honestly rather than avoiding an awkward conversation. Far more important is vesting: founder shares that vest over time — commonly four years — so that a co-founder who leaves after six months doesn't walk away with a quarter of the company for a few months' work. Vesting protects the founders who stay and reassures investors that the team is committed. Skipping it is one of the most common and most damaging early mistakes, and it's almost impossible to fix once someone has already left with unvested-but-unrestricted shares.
The mistakes that wreck a cap table
A few errors compound painfully. Giving away too much too early — handing a big slice to an advisor, an agency or a first investor at a low valuation — leaves you with little room to raise later without demoralising dilution. Messy or missing paperwork turns a future funding round or acquisition into a due-diligence nightmare that can kill the deal. No vesting leaves the company exposed to departing founders. And an overcomplicated table stuffed with tiny holders and odd side deals scares off clean investors. A cap table is hard to fix retroactively because every past decision is baked into someone's ownership; the time to keep it clean is always now.
Why clean records matter at every raise
Every time you raise money or contemplate a sale, the first thing a serious counterparty does is scrutinise your cap table. Ambiguity there — unclear ownership, undocumented promises, informal equity handshakes — reads as risk and either lowers your valuation or scuppers the deal. A clean, accurate, well-documented cap table does the opposite: it signals a company that's run properly and can be invested in or acquired without drama. The founders who treat their cap table as a living, carefully-maintained record rather than something to reconstruct in a panic before a raise consistently move faster and negotiate from strength when it counts.
A clean cap table starts with a clean company — where doola does more
Modelling ownership and dilution is exactly what this calculator is for, and understanding the arithmetic before you raise is worth real money at the negotiating table. But a cap table only means something if the company beneath it is properly formed and documented — the right entity, clean incorporation, an EIN, and compliant records that hold up when an investor's lawyers start digging. That's where a service like doola does more: it handles business formation, tax and compliance paperwork so your equity story sits on solid legal ground rather than a pile of informal arrangements. Use this tool to model the numbers; use a formation and compliance service to make sure the company they describe is real, clean and investable.
Frequently asked questions
What is a cap table?
A capitalisation table lists who owns what share of your company. After each funding round it shows the updated ownership split between founders and investors.
How does a funding round dilute founders?
New shares are issued to the investor, increasing the total. Your share count stays the same but the total grows, so your percentage drops — even though the company (and your stake's value) is usually worth more.
Does this include the option pool?
No — to keep it clear it models founders and investors only. Real rounds usually add or expand an employee option pool, which dilutes founders a bit more. Factor that in separately.
How do I keep more of my company?
Raise less, raise at a higher valuation, or raise later once you've de-risked. And get the legal setup right early — a service like doola helps with formation and the back office.
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