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SaaS Ownership Calculator

The SaaS Ownership Calculator estimates the post-financing ownership percentages of existing holders, a new investor, and an option pool using pre-money valuation, investment size, and current ownership. It is a percentage-based planning model that avoids requiring a full share ledger.

The tool is useful for comparing term-sheet scenarios and understanding how a financing reallocates the fully diluted ownership pie. Existing holders are first reduced by any incremental pre-money option-pool dilution, then diluted by the new investor’s post-money stake. The result is a simplified capitalization view; actual ownership should be confirmed with a detailed cap table that includes every security and transaction term.

Ownership scenario

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USD
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Result
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Existing holders after financing
New investor ownership—
Total pool / other ownership—
Post-money valuation—
Ownership total—

1. Enter the current ownership split
Founders/existing holders and existing option pool or other holders must total 100%.

2. Enter pre-money valuation
Use the negotiated value before new capital is invested.

3. Enter the new investment
The calculator converts the investment into a post-money investor ownership percentage.

4. Add incremental pool dilution
Use this field for a new pool top-up imposed before the financing, not the pool already included in the current split.

5. Review the post-financing allocation
The output shows existing holders, the combined pool/other ownership, and the new investor.

6. Verify the 100% check
A total near 100% confirms that the simplified ownership allocation is internally balanced.

Investor ownership = Investment ÷ (Pre-money valuation + Investment)
Existing-holder factor = (1 − New pool dilution) × (1 − Investor ownership)
Final existing-holder ownership = Current existing-holder ownership × Existing-holder factor

The existing option pool is diluted by the same factor as other pre-financing holders. The newly added pool is also diluted by the financing because it is modeled immediately before investor issuance.

What the result means

The main result is the founders’ and other selected existing holders’ combined ownership after the modeled transaction.

The model assumes primary issuance and does not include convertibles, warrants, secondary sales, or class-specific rights.

Given: Existing holders own 82%, existing pool/others own 18%, pre-money valuation is $15 million, investment is $5 million, and added pool dilution is 5%.

Calculation: Investor ownership = $5M ÷ $20M = 25%. Existing-holder factor = 95% × 75% = 71.25%. Final existing holders = 82% × 71.25% = 58.425%.

Result: Existing holders own approximately 58.43% after the financing.

Why must the current ownership inputs total 100%?

The tool allocates the entire pre-financing ownership base between the two current groups. A different total would make the post-financing allocation incomplete.

Is the new option pool added to the existing pool?

Yes. The output combines the diluted existing pool/other group with the modeled new pool allocation.

Does the investor percentage depend on the option pool input?

In this simplified percentage model, investor ownership is investment divided by post-money valuation. The pool changes how the remaining ownership is divided among pre-financing holders.

How should secondary shares be modeled?

They are not handled here. A secondary purchase transfers ownership between holders rather than adding primary capital, so it requires a more detailed cap-table model.

How is ownership different from implied equity value?

Ownership is a percentage of the company. Implied equity value applies that percentage to a valuation, but actual liquidity proceeds can differ because of preferences and transaction terms.