Fundraising
Understand equity dilution
See how issuing new shares changes ownership percentages, with a worked funding-round example and an explanation of option pools and convertibles.
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What dilution means
Ownership dilution occurs when the number of shares counted in a company increases while a holder’s share count stays the same. The holder owns a smaller percentage of the larger total.
Dilution describes a percentage change. It does not, by itself, establish whether the monetary value of the holding has increased or decreased. A financing can change both the company’s capitalization and its implied value.
A simple funding-round example
Assume a company has 10,000,000 shares before a round. A founder owns 6,000,000 shares, or 60%. Investors propose a $2,000,000 investment at an $8,000,000 pre-money valuation.
This example has one share class and excludes convertibles, option-pool changes, anti-dilution adjustments, fees, and secondary sales.
- Price per share: $8,000,000 ÷ 10,000,000 = $0.80.
- New investor shares: $2,000,000 ÷ $0.80 = 2,500,000.
- Post-round total: 10,000,000 + 2,500,000 = 12,500,000 shares.
- Founder ownership: 6,000,000 ÷ 12,500,000 = 48%.
| Holder | Before | After |
|---|---|---|
| Founder | 60% | 48% |
| Other existing holders | 40% | 32% |
| New investors | 0% | 20% |
Percentage points and relative dilution
The founder’s ownership falls from 60% to 48%. That is a decrease of 12 percentage points. Relative to the original 60% stake, the decrease is 20%: (60 − 48) ÷ 60.
The founder still holds 6,000,000 shares. The denominator changed. Distinguishing the share count, percentage-point change, and relative change prevents different uses of “dilution” from being confused.
Why actual rounds can differ
A pre-money option-pool increase expands the capitalization used to price the financing. It can therefore dilute existing holders in addition to the shares issued for new investment. Cooley’s option-pool explanation works through why the size and timing of the pool matter.
SAFEs and convertible notes can also add shares at conversion. The outcome depends on the instrument’s terms, including any valuation cap, discount, and capitalization definition. Pre-money and post-money SAFE calculations are not interchangeable. Y Combinator publishes its SAFE documents and explanatory materials.
These additional terms are why the simple example should not be applied unchanged to every financing. Review each instrument and the actual financing documents.
Compare scenarios in Cap Table
Use Round modeling to enter the pre-money valuation, investment amount, and unallocated-pool target. The model uses recorded securities and instrument terms to calculate the proposed capitalization.
Compare the before-and-after view by holder. Change one assumption at a time and record which terms each saved scenario represents. Saving a scenario does not close the financing or alter the cap table.
Follow Model a funding round for the workflow and the review required before applying a close.