Find the row that matches what just happened in your equity comp, then click through to the right calculator. Each calculation runs in your browser — no signup, nothing leaves your device.
If…
Your RSUs just vested and you want to know what you owe
Then use
📈 RSU Tax Withholding Shortfall Calculator →Estimate the gap between the 22% federal supplemental withholding and your real marginal rate
Background reading: /blog/how-much-tax-will-i-pay-on-rsu
If…
You got a cash bonus and the withholding looks too low
Then use
💵 Bonus Tax Withholding Shortfall Calculator →Same engine as RSU shortfall, applied to cash bonuses paid as supplemental wages
If…
You exercised ISOs (or are about to) and worry about AMT
Then use
⚡ ISO Exercise AMT Calculator →Compute Alternative Minimum Tax exposure on the bargain element
If…
You exercised ISOs in a prior year and want to recover the AMT credit
Then use
♻️ AMT Credit Recovery Calculator →Project Form 8801 minimum tax credit recovery year-by-year
If…
You exercised non-qualified stock options (NSOs)
Then use
🎯 NSO Exercise Tax Calculator →Compute the bargain element + ordinary income + FICA + withholding gap
If…
You sold ESPP shares and want to know if it was a qualifying disposition
Then use
🧾 ESPP Qualifying Disposition Tax Calculator →Split the gain into ordinary income vs long-term capital gain under §423
If…
You owe estimated tax and want to hit the IRS safe harbor
Then use
🗓️ Quarterly Estimated Tax Safe-Harbor Calculator →Compute IRC §6654 quarterly payments to avoid the underpayment penalty
Background reading: /blog/estimated-tax-after-rsu-vest
If…
You want to compare state tax rules for equity comp before moving
Then use
🗺️ State Stock-Comp Tax Lookup →Top marginal, supplemental withholding, AMT, LTCG rules by state
Background reading: /blog/rsu-taxes-by-state
Still not sure?
The two most common starting points are RSU Tax Shortfall (for anyone with RSU vests) and Quarterly Estimated Tax (for anyone who owes more than $1,000 at filing). If your situation is more complex — check the glossary for the terms, or tell us your situation and we'll point you at the right tool.
Spotted a bug, edge case, or numbers that look off? Tell us — we read every report.