Startup Equity Calculator
What your stock options or RSUs are worth, one number at a time.
An offer that says “40,000 options” tells you very little on its own. Enter the numbers from your offer and this calculator shows what the grant is worth at today’s price, what you keep if you leave early, and what it could be worth if the company is sold or goes public. Each field explains what it means. It runs entirely in your browser, with no signup. If you’re negotiating the salary too, the salary counter offer calculator covers the cash side.
Stock options are the right to buy shares later at a fixed price. RSUs (restricted stock units) are shares you receive as they vest, with nothing to pay. Your offer letter says which.
What you pay for each share when you turn an option into a share. It is fixed on the day the options are granted, usually at the 409A value on that day.
Ask the company for it. A startup usually has two prices, and they mean different things.
409A value: an independent valuation of the company’s common stock, the kind employees hold. It is usually refreshed every year or after a funding round, and it is usually the lower number.
Last preferred price: what investors paid per share in the latest funding round. Their preferred shares carry extra rights, such as being paid back first in a sale, so this price is usually higher than what a common share is worth.
Stock market price: if the company is already listed on a stock exchange, use today’s share price.
We never send or store any of this. The math runs entirely in your browser, no account needed.
Every share that exists or has been promised, including all options. Your shares divided by this is your ownership. Ask for it: without it, 40,000 options could be 0.4% of the company or 0.004%, and the exit cases below can’t be worked out.
Vesting
Vesting is how you earn the grant over time. The cliff is how long you have to stay before any of it vests; leave earlier and you get nothing. Four years with a one-year cliff is a common schedule.
Future funding
Each funding round creates new shares for the new investors, so your slice of the company shrinks while your share count stays the same. These defaults are only a starting assumption; change them if you know more.
Exit
What your grant is worth
At today’s price
What this means
If you leave early
| If you leave at | Yours | Value at today’s price |
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If the company is sold or goes public
These are estimates from the numbers you entered. They are not tax, legal or investment advice.
They leave out tax. In the US, exercising incentive stock options (ISOs) can trigger the alternative minimum tax, exercising non-qualified options (NSOs) is taxed as ordinary income on the gap between price and strike, and RSUs are taxed as income when they are delivered. They leave out liquidation preferences, which pay investors back before common shareholders, so in a modest sale your shares can receive less than the headline price, or nothing. Many startups never reach a sale or listing that pays common shareholders at all, and then the grant is worth nothing.
A grant you can value is a grant you can negotiate. More shares, a shorter cliff and a longer exercise window are all fair asks. Rehearse the conversation first, against an AI hiring manager who pushes back like a real one.
Practice the equity conversationFree to start, no card needed. Or read how the job offer scenario plays out first.
Questions to ask before you sign
Most of what decides a grant’s value isn’t in the headline number. Ask for these in writing.
- Fully diluted shares. The total that turns your share count into a percentage. Ask: “What percentage of fully diluted shares does this grant represent?”
- The 409A value and the last preferred price. The first is roughly what a common share is worth today; the second is what investors paid. You need both to read the grant.
- Vesting and cliff. How many years, how long the cliff is, and whether vesting after the cliff is monthly or quarterly.
- Post-termination exercise window. How long you have to exercise vested options after you leave. A short window can mean finding the exercise cost, and any tax, within weeks.
- Acceleration on acquisition. Whether unvested equity vests early if the company is bought. Single-trigger acceleration vests on the sale itself; double-trigger also needs you to be let go after the sale.
- Liquidation preferences. How much investors get back before common shareholders in a sale. In a modest exit this decides what your shares receive.
The guide to negotiating equity and stock options covers how to ask for each of these, and what to do with the answers.
How the calculator works
Options are worth the gap between the share price and your strike, times the number of options, and never less than zero. RSUs are worth the full share price times the number of units.
Options today = options times (current price minus strike), at least 0 RSUs today = units times current price Ownership = your shares divided by fully diluted shares Kept after dilution = (1 minus dilution per round), once for each round Price per share at exit = company value times kept, divided by today’s fully diluted shares Value at exit = shares times (exit price minus strike), at least 0A worked example. You’re offered 40,000 options with a $1.00 strike. The 409A value is $1.50 and there are 20,000,000 fully diluted shares. You own 0.2% of the company, and the paper value today is 40,000 times $0.50, or $20,000. Exercising all of it would cost $40,000. After two more rounds at 20% each you keep 64% of that stake, or 0.128%. If the company then sells for $300,000,000, each share is worth $9.60 and your options are worth 40,000 times $8.60, or $344,000 before tax and before any liquidation preferences. Leave at 11 months and all of that is zero.
Common questions
What are my stock options worth?
On paper, the number of options times the gap between the current share price and your strike price, and never less than zero. At a private company the cautious current price is the 409A value, and a new grant’s strike is usually set at that value, so a fresh grant is often worth close to nothing on paper today. What it could be worth depends on what the company is eventually sold or listed for, how much more it raises before then, and the terms its investors hold. Until there is a sale or a listing, startup shares usually can’t be sold.
What is the difference between the 409A value and the preferred price?
The 409A value is an independent valuation of a private company’s common stock, the kind employees hold. It is named after the section of the US tax code that requires it, and companies use it to set option strike prices. The preferred price is what investors paid per share in the last funding round. Preferred shares come with extra rights, such as being paid back first in a sale, so the preferred price is usually higher than the 409A value. Use the 409A value for a cautious read of what your shares are worth, and treat the preferred price as an upper bound.
What happens to my stock options if I leave the company?
Unvested options go back to the company, and if you leave before the cliff you keep none of them. Vested options stay yours for a limited time: you usually have to exercise them within a set window after leaving, often 90 days, or they expire. Exercising means paying the strike price for each share, and in the US it can also trigger tax. Some companies offer a longer window, which is worth asking for before you sign.
What is the difference between RSUs and stock options?
Stock options are the right to buy shares at a fixed strike price. They are worth only the amount the share price rises above that strike, and you pay to exercise them. RSUs (restricted stock units) are a promise of shares delivered as they vest, with nothing to pay, so they keep some value as long as the shares are worth anything. Startups more often grant options; larger and listed companies more often grant RSUs. The two are taxed differently, which this calculator leaves out.
How does dilution affect my equity?
When a company raises a funding round it issues new shares, so every existing holder owns a smaller percentage while their share count stays the same. If a round sells 20% of the company, everyone keeps 80% of their previous stake, and two such rounds leave 64%. Dilution does not have to lower what your shares are worth, because the money raised is meant to make the company more valuable, but it does mean the percentage you hold today shrinks before any exit.
Where do my numbers go?
Nowhere. The math runs entirely in your browser. This page never sends or stores what you type, and no account is needed to calculate.
Read these numbers as estimates
What equity pays depends on events no one can predict, and on tax rules and investor terms that differ by country and by company. This tool multiplies the numbers you supply. Before you exercise options, sell shares or trade salary for equity, talk to a tax or financial adviser.