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Vesting Schedule Calculator

Calculate equity vesting schedules with cliff period, vesting duration, acceleration triggers, and unvested share forfeiture modeling.

Tested tool guide Tested browser tools Checked August 16, 2026

What Vesting Schedule Calculator does, with a checked example

This calculator turns a grant into a dated list of shares: enter total shares, vesting duration, cliff, and vesting frequency, and it returns how many shares vest on each date plus what you hold at any departure month. It also models single- and double-trigger acceleration and the unvested share forfeiture on early exit. The surprise is usually the cliff: with a one-year cliff on a four-year grant, 25% of the shares vest in one lump at month 12 and the rest monthly after, so nothing vests in the first year even though total time to 100% is unchanged.

Worked example

A concrete input and expected output from the current implementation.

Input

Grant: 1,200 shares. Vesting: 48 months. Cliff: 12 months. Frequency: monthly. Departure month: 20.

Expected output

Cliff event at month 12: 300 shares (25%). Then 25 shares per month. Vested at month 20: 500 shares (41.7%). Forfeited on departure: 700 shares (58.3%).

The cliff tranche is 25% of the grant, matching 12 of 48 months. The remaining 900 shares spread over the 36 post-cliff months at 25 per month, so month 20, eight months after the cliff, holds 300 plus 200 shares, and the unvested 700 are forfeited.

How the result is produced

1

Schedule construction

The grant is split into two tranches. The cliff tranche, equal to the cliff fraction of the total (a 12-month cliff on a 48-month grant is 25%), vests as one event on the cliff date. The remainder divides evenly across the months or quarters after the cliff. The vested total on any date is the cliff tranche plus elapsed post-cliff periods times the per-period amount, rounded to whole shares.

2

Forfeiture and acceleration

Departure is evaluated month by month. Before the cliff date the report is 0% vested and the full grant forfeited; after it, the vested portion is shown as yours and the remainder as forfeited. With double-trigger acceleration enabled, a change of control followed by termination within the stated window converts the unvested shares to vested, and the schedule recomputes forward from the acceleration date.

Good uses

  • Evaluate a job offer's equity: enter the grant terms and see how many shares you would hold after one, two, or three years, and what a departure before year four would forfeit.
  • Compare competing offers with different shapes, such as a four-year schedule with a one-year cliff versus a three-year schedule, at the same calendar date.
  • Stress-test an acquisition: with double-trigger acceleration on, find how many shares vest if a change of control followed by termination lands in a given month.

Limits and checks

  • The schedule assumes full-time, continuous service from the grant date. Leaves of absence, part-time service, and start dates later than the grant date all shift the real vesting dates, and many plans count service from the hire date even when the grant is dated later.
  • The output is share counts, not value. What you net depends on the share price on each vest date and on the tax character of the grant: an ISO, an NSO, or restricted stock with an 83(b) election are taxed very differently, and exercising options costs cash.
  • Acceleration language varies by plan. The calculator's double trigger is a stated assumption, usually change of control plus termination within 12 months, but the actual plan document defines the window, the percentage accelerated, and whether the change of control alone qualifies. The grant agreement governs.

Common questions

I leave after the cliff but before the grant is fully vested. What do I actually keep?

The vested shares are yours, and the calculator shows the count at your departure month; the unvested shares are forfeited. Two practical caveats: the company often holds a right to repurchase vested shares within a window after you leave, and turning options into shares requires exercising them, which costs cash and starts the tax clock. The schedule is share counts, not what you net.

Does a one-year cliff really mean I lose a year of vesting?

No. On a standard four-year grant, the cliff month vests the full first-year tranche, 25%, in a single event, and each of the remaining 36 months adds one-thirty-sixth of the rest, so you are still fully vested at month 48. The cliff changes the shape of the schedule, not the total. What it does mean: leaving in month 11 forfeits everything, because no shares vest before the cliff.

References and verification

The example and behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.

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