Equity compensation, worked out properly

Calculators

• 01 Calculator 83(b) Election Calculator Filing an 83(b) election taxes you now, on today’s value, instead of at each vesting date on whatever the shares are worth then. Usually that is a large win. Occasionally it is a disaster you cannot undo. This prices both paths. Lifetime tax saved by electing · Tax due within 30 days
• 02 Calculator AMT Credit Recovery Calculator Paying alternative minimum tax on an ISO exercise creates a minimum tax credit that never expires. It also never arrives all at once. §53 releases it only in years where your regular tax exceeds your tentative minimum tax, which for most people is a few thousand dollars a year — until the shares are sold. Years to recover it all · Credit you can claim each year
• 03 Calculator ESPP Disposition Calculator Sell your employee stock purchase plan shares too early and the whole discount is ordinary income — even if you sold at a loss. This works out what each path costs, and whether holding on is actually worth it. Tax this sale costs you · Net proceeds after tax
• 04 Calculator Exercise Financing Break-Even Calculator Non-recourse lenders will pay your strike price and your tax bill in exchange for interest and a share of the upside. Whether that is a lifeline or an expensive mistake depends on the exit price — and the honest comparison is not against paying cash, but against doing nothing at all. Net if you pay cash · Net if you finance
• 05 Calculator ISO AMT Calculator Exercising an incentive stock option produces no regular taxable income and can still produce a very large tax bill. This works out the alternative minimum tax, the total cash you need, and the largest exercise you can make without triggering AMT at all. AMT caused by this exercise · Total cash needed
• 06 Calculator NSO Exercise Cost Calculator Exercising a non-qualified stock option is a taxable event the moment you do it. Your company has to collect the withholding before it will issue the shares, so the bill is not deferred to April — it is due now. This works out how much, and whether you can cover it. Cash needed on the day · Shares to sell to cover it
• 07 Calculator Offer Comparison Calculator An offer letter values your equity at shares times today’s price. That figure ignores the strike you have to pay, the tax you will owe, and the possibility that a private company’s shares end up worth nothing. This prices both offers on the same basis. Advantage to Offer A · Offer A’s equity must be this likely to tie
• 08 Calculator QSBS Eligibility & Exclusion Calculator Section 1202 can exclude millions of dollars of gain from federal tax entirely. It is also the most conditional provision an ordinary shareholder will ever meet: six tests, two entirely different regimes depending on whether you acquired the stock before or after 4 July 2025, and a rate trap in the middle of the new one. Share of gain excluded · Tax saved by qualifying
• 09 Calculator RSU Withholding Shortfall Calculator Your employer withholds a flat 22% on vesting RSUs regardless of what you actually earn. If your real rate is 32% or 35%, the difference is a bill you meet in April. This works out exactly how large it is. Additional tax you will owe · Shares to sell to cover it
• 10 Calculator Tender Offer & Secondary Sale Calculator A tender offer is usually the first time startup equity turns into money. What you keep depends far less on the price than on what you were holding when the offer arrived — and on whether anything was withheld before the cash reached you. Net cash you keep · Cash that reaches you at closing

Guides

The longer explanations behind the calculators — what the rules say, and where they catch people out.

• 01 Guide Double-trigger RSUs, and the bill that arrives at IPO Private-company RSUs need two things to happen before you own anything: time, and a liquidity event. That structure protects you from being taxed on shares you cannot sell — and stores up several years of income to land in a single tax year when the company finally goes public.
• 02 Guide What changed for equity compensation in 2026 Two provisions that matter enormously to people holding startup equity were rewritten in July 2025, and both took effect for 2026. One makes exercising incentive stock options more expensive at high incomes. The other makes founder stock dramatically more valuable — but only if it was issued after a particular Friday.
• 03 Guide The tax forms your equity generates Equity compensation produces a small pile of paperwork every spring, most of it informational and one piece of it actively misleading. The 1099-B your broker files frequently reports a cost basis of zero on shares you have already paid tax on, and correcting it is on you.
• 04 Guide How equity compensation is taxed Four instruments, four completely different answers. What decides your tax is not how much your equity is worth but which of the four you hold, and at which of the four possible moments the tax code decides to notice it.
• 05 Guide What happens to your options when you leave Resigning starts two clocks at once. One gives you ninety days to find the cash to exercise or lose the options entirely. The other, which almost nobody is told about, quietly converts incentive stock options into non-qualified ones on day ninety-one.
• 06 Guide When to exercise your stock options The strike price is fixed and the deadline is years away, so exercising feels like a decision you can defer indefinitely. It is not: every year you wait usually raises the valuation, and the tax you will owe rises with it. Here is what actually drives the timing.

Why another calculator site

Equity compensation is where generalist tax tools quietly get things wrong. The maths is fiddly, the rules changed materially for 2026, and the audience is small enough that the large personal-finance publishers do not staff it. Most of what exists is either a marketing page with a form attached or a calculator that has not been updated since the rules changed.

This site takes the opposite approach. The method is shown on every page. Every rate traces to the statute, the regulation, or an IRS publication. Nothing you type leaves your browser, and there is no email gate, no account, and no lead form. Where a figure has not been verified to our own standard, the option that would use it is not offered at all.

The verification is not a claim — it is machinery, and you can read exactly what it does. Right now that is 69 hand-verified test cases across 10 calculators, plus 2000 randomised draws per calculator checked against declared invariants.