Navigate the tax complexity of equity comp in the right order. RSU withholding gap first — the most common surprise. ISO AMT exposure before exercising. ESPP sell timing with qualifying vs. disqualifying disposition comparison. 2026 tax parameters throughout.
Start here because this affects the largest population and surprises the most people. The IRS requires companies to withhold at the 22% supplemental rate on RSU vests — but if your marginal rate is 32%, 35%, or 37%, you owe the gap at tax time. This tool calculates the federal gap, FICA exposure above the $184,500 SS wage base (2026), NIIT threshold proximity, and state gap using simplified buckets. The output tells you whether to request additional withholding, make a Q4 estimated payment, or sell-to-cover extra shares.
Open RSU Withholding Gap Calculator →ISO exercise spreads create AMT income — the difference between FMV and strike price is an AMT preference item. Using 2026 AMT parameters (exemption $90,100 single / $140,200 MFJ, phase-out starts at $500k/$1M, 26%/28% two-rate bracket), this tool finds the maximum shares you can exercise with zero AMT liability. Above that threshold, it shows the exact AMT bill for any exercise quantity. Binary search precision: the safe zone is calculated to the share.
Open ISO AMT Exposure Modeler →ESPP disposition rules are frequently misunderstood. A qualifying disposition requires holding >2 years from offering AND >1 year from purchase — and taxes the lesser of (sale price − purchase price) or (offering price − purchase price) as ordinary income. A disqualifying disposition taxes FMV-at-purchase − purchase price as ordinary income, full stop. This tool compares after-tax proceeds under both paths, finds the break-even sale price where holding to qualify becomes worthwhile, and layers 2026 LTCG rates on top of ordinary income for each scenario.
Open ESPP Break-Even & Optimal Sell Analyzer →