How VestWiz works

Three steps: add your equity, see your true tax picture, and stay on track all year. The free calculators run entirely in your browser — nothing leaves your device.

Step 1

Add your equity

Enter your RSU vests, ISO exercises, and ESPP purchases in the free calculator — manually, or import them in seconds from a broker template (CSV or Excel). No account, no sign-up, no data sent anywhere.

Open the calculator →

Step 2

See your true tax picture

RSU withholding gap

The 22% trap

Your employer withholds a flat 22% on every vest. If your marginal rate is 24%, 32%, or higher, you owe the difference every April — the calculator shows the exact shortfall.

ISO / AMT exposure

The exercise surprise

Exercising incentive stock options triggers no regular tax — but the spread counts for AMT. The advanced worksheet walks through Form 6251 line by line, plus the Form 8801 AMT credit.

ESPP tax split

Ordinary vs. capital

See exactly how much of your ESPP gain is ordinary income versus capital gain — including the qualifying vs. disqualifying disposition tests.

Estimated payments

The quarterly plan

Under-withheld equity income can mean quarterly estimated payments. The planner computes your safe-harbor target and per-quarter amounts so you avoid underpayment penalties.

Step 3

Stay on track with Pro

The free calculator shows you the gap once. VestWiz Pro keeps it all in one place for $199/year:

Vest tracker

Log every vest and see its withholding-gap recalculation automatically, with charts of your vest income and tax gap.

Quarterly reminders

Email reminders before each estimated-payment deadline — never miss an IRS date again.

Planning tools

Black-Scholes exercise timing, job-offer comparison + negotiation playbook, year-end planner, ISO/AMT exposure checks, and the AMT credit tracker.

Clean export for tax time

Every event in one CSV download — plus a CPA tax packet you can print or email to your accountant.

Get VestWiz Pro — $199/year

14-day money-back guarantee. Secure checkout via Stripe. Cancel anytime — you keep Pro until the end of your billing year.