Vesting Calculator

When a startup gives you stock options, it rarely gives them to you all at once. Instead, the grant vests over time: you must keep working for the company before you are allowed to exercise — and keep — any of it. This vesting calculator shows exactly how many of your options have vested today, how much it would cost to exercise them, and what the vested portion is actually worth if the company's current share price is above your strike.

The model below is the venture-capital standard: a one-year cliff, then equal monthly installments for the remaining schedule. Type your grant numbers in the form and the result card updates instantly.

How to Use

1. Enter the Stock Options Granted — the total number of options or RSUs in your grant, as printed on your offer letter or equity agreement.
2. Type the Strike Price (Exercise Price) — what you will pay per share when you exercise. For private companies this is usually the 409A fair market value on the grant date.
3. Add the Current Price Per Share so the calculator can show your paper spread. Leave it at 0 for a private company with no recent priced round.
4. Choose the Vesting Period — most US startup grants vest over 4 years; some public-company RSU grants run 3 or 5 years.
5. Set the Cliff Period. The standard US startup cliff is 1 year: if you leave on day 364, nothing vests; if you stay one more day, a full chunk vests at once.
6. Enter Years Worked Since Grant — time from the grant date to today. Fractional years work, so 2.5 is fine.

The result card breaks out your vested percentage, the lump that vested at the cliff, how many options vest each month afterward, the cash you would need to exercise everything vested, and the intrinsic (in-the-money) value of that vested portion.

The VC-Standard Vesting Schedule

Almost every early-stage US option grant follows the same recipe:

• A 1-year cliff. For your first 12 months, nothing vests. Stay through the first anniversary and a block equal to cliffYears / vestingYears of the grant vests all at once — typically 25% on a 4-year schedule.
• Monthly installments after the cliff. The remaining 75% then vests in equal monthly pieces. On a 4-year schedule that is 36 more monthly tranches, each worth 75% / 36 ≈ 2.083% of the grant.
• Full vesting at the end of the schedule. After 4 years, 100% of the grant is yours.

Worked example: 10,000 options at a $10 strike. At the 1-year cliff, 2,500 options (25%) vest. From month 13 onward, 7,500 ÷ 36 ≈ 208.33 options vest every month. After 2 years, you have the 2,500 cliff block plus 12 monthly tranches of 208.33 — another 2,500 — for 5,000 options, exactly 50% vested. At a $10 strike, exercising those 5,000 options costs $50,000, against a full-grant exercise price of $100,000.

Why the Cliff Matters

The cliff exists to protect the company. An engineer who joins, gets a 0.5% option grant, and quits three months later should not walk away with equity the founders intended for long-term contributors. The trade-off for you: leaving just before the cliff is extraordinarily expensive. On the 10,000-option example above, departing at month 11.999 means $0 vested; staying until month 12 suddenly makes 2,500 options (worth a $25,000 exercise position) yours.

When you negotiate an offer, ask two questions: how long is the cliff, and does the company use a "double-trigger acceleration" clause — meaning the options vest immediately only if you are fired without cause and the company is acquired. That clause is worth real money in an acquisition.

Strike Price vs. Current Price: What Your Options Are Really Worth

Two dollar numbers matter on your grant paperwork:

• Strike (exercise) price — what you pay. Set by a 409A valuation for private companies; for ISO grants this is legally required to equal fair market value, or the options lose their special tax treatment.
• Current price — what the stock is worth today. For public companies it is the live market quote. For private companies it is the price paid in the most recent preferred round, heavily discounted because preferred stock has rights common options do not.

Your intrinsic value on the vested portion is simply vested options × max(0, current price − strike). If your strike is $10 and the latest round priced the stock at $30, each vested option carries a $20 paper spread. On 5,000 vested options that is $100,000 of intrinsic value — before taxes, before the cost of exercising, and before any liquidity event.

Examples

Example 1 — The standard two-year mark. You were granted 10,000 options at a $10 strike on a 4-year schedule with a 1-year cliff, and today you are 2 years in with the latest round at $30. The calculator reports 5,000 options vested (50%), a $25,000 cliff block, roughly 208 options vesting each month, a $50,000 exercise cost, and $100,000 of intrinsic value. You still hold 5,000 unvested options you would forfeit by leaving.

Example 2 — Leaving just before the cliff. Same grant, but you are 11 months in. The calculator reports 0 options vested and $0 intrinsic value. The entire 10,000-option grant — worth up to $200,000 of spread at $30 — disappears the day you walk out the door.

Example 3 — Fully vested at four years. A 1,000,000-option grant at a $2 strike, 4-year schedule, 1-year cliff, 4 years worked. The calculator reports 1,000,000 options vested (100%), a $2,000,000 total exercise cost, and if the current price is $5, $3,000,000 of intrinsic value. This is the payoff the schedule was designed to deliver — but only if you stayed the full four years.

Example 4 — Fractional time worked. Halfway between the cliff and year 2 (1.5 years), you hold the 2,500-option cliff block plus 6 monthly tranches of 208.33: 3,750 options, 37.5% vested, costing $37,500 to exercise and carrying $75,000 of intrinsic value at a $30 current price.

FAQ

How does 4-year vesting with a 1-year cliff work?

Nothing vests during the first year. On the first anniversary of your grant, a block equal to 25% of the grant vests all at once. The remaining 75% then vests in equal monthly installments over the next 36 months, so that 100% is vested at year four. This is the standard US venture-capital schedule.

What happens to my options if I leave before the cliff?

You forfeit the entire grant. On a 4-year schedule with a 1-year cliff, leaving at month 11 means zero options have vested — the company cancels all of them. Staying one day past the cliff vests the whole 25% block at once, which is why the cliff date is the single most important milestone on your equity calendar.

How much do I need to pay to exercise my vested options?

Multiply your vested options by your strike price. If 5,000 options have vested and your strike is $10, exercising them costs $50,000 out of pocket — plus exercise fees and, for ISOs held past exercise, potential Alternative Minimum Tax. Use the "Cost to Exercise Vested Options" line on this page to see your exact number.

What is the difference between strike price and current price?

Strike price is what you pay per share to exercise; it is fixed on your grant paperwork and usually set by a 409A valuation for private companies. Current price is what the stock is worth today. Your actual profit per share is the spread: current price minus strike. If the current price is at or below your strike, your options have zero intrinsic value even if they have fully vested.

Do RSUs vest the same way as stock options?

RSUs almost always use the same cliff-plus-monthly schedule, but they work differently economically: an RSU is a share granted to you for free as it vests, taxed as ordinary income at the vest date, with no exercise price. A stock option requires you to pay the strike to obtain the share. The vesting math (percent vested by date) is identical; this calculator applies to both, but the "Cost to Exercise" line is most meaningful for options.

Can my vesting schedule be changed after I sign?

The schedule in your grant agreement is contractual and cannot be retroactively changed without your consent. What companies can do is grant you a new "refresh" award when you stay beyond the original schedule — often to replace the unvested portion of your old grant — which starts its own new cliff. Always confirm refresh terms before assuming old options keep vesting past their original end date.

Disclaimer

This vesting calculator is provided for informational purposes only and does not constitute financial, tax, legal, or investment advice. It models the standard 4-year, 1-year-cliff schedule and assumes equal monthly installments; your actual grant agreement may use quarterly tranches, a different cliff, performance conditions, acceleration clauses, or a post-termination exercise window that this tool cannot reflect. Intrinsic-value figures ignore taxes, 409A haircuts, illiquidity discounts, and the risk that a private company never has a liquidity event. Confirm your vested balance, strike, and tax treatment directly with your equity administrator and a qualified tax professional before exercising any options.