What is the strike price?

Also called the exercise price — the per-share price you pay to convert options into shares. It's set by the company's 409A valuation at grant time and doesn't change.

What's the difference between options and RSUs?

Options give you the right to buy shares at the strike price — you only profit if the share value rises above it. RSUs (Restricted Stock Units) are granted at no cost — they're worth the full share value at vesting.

How does future dilution affect my payout?

Each new funding round issues new shares, diluting everyone proportionally. If you own 1% today and the company raises 3 more rounds each diluting 20%, your final ownership is 1% × 0.8 × 0.8 × 0.8 = 0.512%.

Does this account for taxes or exercise costs?

We show gross proceeds (exit value − strike cost). Actual taxes depend on your grant type (ISO/NSO/RSU), holding period, and jurisdiction — often 20-50% of the gain. Consult a tax advisor before exercising.

What if the exit value is below my strike?

Your options are “underwater” — exercising would lose money. You'd simply not exercise, and the options expire worthless. Most employee options have a 10-year expiration window.

Are my equity details uploaded?

No. The math runs 100% in your browser. Refresh to clear — your grant details are sensitive, treat them accordingly.

Startup Equity Calculator

Estimate the value of your employee stock options after dilution and exit.

100% private — no uploads Free & unlimited Read tutorial

See how it works

Watch a quick simulation of this tool in action — no file needed.

How to use Startup Equity Calculator

Follow these steps — everything happens instantly in your browser.

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Step 1. Enter your option grant: number of shares and strike (exercise) price.
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Step 2. Enter the company's current fully-diluted share count and latest 409A valuation.
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Step 3. Set an expected exit valuation and additional dilution from future rounds.
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Step 4. Read your proceeds, ROI, and effective ownership at exit.

Why use this tool

Frequently asked questions

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