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Your employer withheld 22%. Your real rate is probably closer to 37%. Find the gap before April finds you.
Your RSUs just vested.
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17 calculators · all free- RSU Tax Shortfallfree · instantRSU Tax Withholding Shortfall CalculatorSee the gap between the 22% (or 37%) your employer holds back when RSUs vest and what you’ll actually owe at your real tax rate.open →
- RSU Cost Basis Fixfree · instantRSU Cost Basis Correction CalculatorBrokers report $0 cost basis on RSU sales, which double-taxes income already on your W-2. See your correct basis (the share price on your vest day), what you’d overpay, and the exact one-line Form 8949 fix.open →
- Double-Trigger RSUfree · instantDouble-Trigger RSU IPO/M&A Tax CalculatorThe tax hit when your pre-IPO startup goes public or gets acquired and your RSUs finally pay out. Federal + state shortfall vs. what’s withheld, shares sold to cover it, and your net cash.open →
- ISO / AMTfree · instantISO Exercise AMT CalculatorEstimate the Alternative Minimum Tax (AMT) when you exercise ISOs, the cash you’ll need, and the credit you get back in later years — plus a sell-the-same-year comparison.open →
- AMT Credit Recoveryfree · instantAMT Credit Recovery CalculatorIf you paid AMT in a past year, you’re owed a credit back. Project how much you recover each year (Form 8801) and when the balance reaches $0, based on your future income.open →
- NSO Exercisefree · instantNSO Exercise Tax CalculatorEstimate the income tax and payroll (FICA) bill when you exercise non-qualified stock options (NSOs) — the “spread” you’re taxed on, what’s withheld, the gap to your real rate, and state tax.open →
- Form 6251 AMTfree · instantForm 6251 AMT Calculator (Multi-Source)Full Alternative Minimum Tax (Form 6251) walkthrough combining your W-2 wages, freelance 1099 income, ISO exercises, and state-tax add-back — to compute the AMT you owe and the credit you get back.open →
- ESPP Qualifying Dispositionfree · instantESPP Qualifying Disposition Tax CalculatorSee how much of your ESPP sale is taxed as regular income vs. the lower long-term gains rate, with federal, state, and the 3.8% investment surtax — and whether holding long enough to “qualify” actually saves you money.open →
- QSBS / §1202free · instantQSBS / Section 1202 Exclusion CalculatorHow much of your startup-stock gain is completely federal-tax-free under the QSBS rule (§1202). Covers the new 2025 tiers (50/75/100%), the dollar cap, the rate on the taxable part, and states that don’t follow it.open →
- Quarterly Estimated Taxfree · instantQuarterly Estimated Tax Safe-Harbor CalculatorFind the “safe harbor” amount you need to prepay to avoid an IRS underpayment penalty, see the schedule quarter by quarter, and get the exact dollar amount to send before the next deadline.open →
- Bonus Tax Shortfallfree · instantBonus Tax Withholding Shortfall CalculatorSee the gap between the flat 22% (or 37%) held back on your cash bonus and what you’ll actually owe at your real tax rate.open →
- W-4 4(c)free · instantW-4 Step 4(c) Extra-Withholding CalculatorTurn a tax shortfall into the exact number to put on your W-4 Line 4(c). Because withholding counts as paid evenly across the year, a late-year fix can retroactively cover the earlier quarters.open →
- State Stock-Comp Lookupfree · instantState Stock-Comp Tax LookupLook up the top tax rate, withholding, AMT, and capital-gains treatment for RSU/ESPP/ISO income in any of the 50 states + DC.open →
- CA 540NRfree · instantCA Form 540NR Apportionment CalculatorVest-by-vest California tax if you moved out of CA (to TX/NV/FL/WA) partway through earning your RSUs — how much California still taxes, the penalty-safe target, and what to prepay.open →
- Mega-Backdoor Rothfree · instantMega-Backdoor Roth CalculatorFind the extra after-tax 401(k) room your plan allows under the $70k total cap — the “Mega-Backdoor Roth” move high earners use for $30–46k/yr of extra Roth savings.open →
- Backdoor Roth IRAfree · instantBackdoor Roth IRA CalculatorCheck if your income is over the Roth IRA limit, and the tax on a “backdoor” conversion if you hold pre-tax IRA money (the pro-rata rule) — plus how to avoid it and a 30-year projection.open →
- Roth Sequencerfree · instantBackdoor + Mega-Backdoor Roth Sequencing OptimizerCombines both Roth moves into one ordered playbook — what to do first, next, and last (clear out pre-tax IRA money, then Mega-Backdoor, then Backdoor) to maximize your tax-free Roth savings for the year.open →
The 22% supplemental flat rate is a floor, not your bracket. Most engineers find a five-figure surprise in their first vest.
Latest from the blog
all posts →- Jun 10, 2026Filing & withholding strategy
RSU wash sale rule: how a vest can quietly disallow your stock loss
Selling company stock at a loss? An RSU vest within 30 days — before or after — counts as an "acquisition" under the wash sale rule and can disallow part of that loss. Here is how the §1091 trap works for RSU and ESPP holders, what gets disallowed, and how to avoid it.
- Jun 9, 2026RSU basics
RSU vested but not released: what it means (and when you can sell)
"Vested" means you have earned your RSUs; "released" (also called settled or distributed) means the shares have actually been delivered to your brokerage account. Here is why there is a gap between the two, when you are taxed, and the pre-IPO case where vested shares stay unreleased for years.
- Jun 9, 2026Filing & withholding strategy
2026 equity comp tax numbers: every rate, bracket, and limit in one place
The verified 2026 figures a tech worker with RSUs, ISOs, NSOs, or ESPP actually needs — federal brackets, standard deduction, the OBBBA-changed AMT, long-term capital gains, FICA wage base, supplemental withholding, and retirement limits. Each number cited to its IRS source.
