stocktax.tools

About stocktax.tools

Free, fast, bilingual calculators for the taxes around U.S. stocks and equity compensation.

In one line: stocktax.tools is a growing collection of free, bilingual calculators for the taxes that catch U.S. stock investors and equity-comp employees off guard — no account, and your numbers never leave your browser.

What is stocktax.tools?

It's a set of browser-based calculators focused on one thing people find confusing and expensive: tax on U.S. stocks and equity compensation. RSU vesting tax and cost basis, ESPP, stock options (ISO/NSO) and AMT, and capital gains — each with the formula shown and the common traps explained, in English and Chinese.

Why we built it

Equity comp is a huge part of pay at U.S. companies, yet the tax mechanics quietly cost people thousands — over-withholding, a broker's $0 cost basis, AMT surprises. Good tools existed in English but were scattered; in Chinese they barely existed at all. We wanted clean, fast, private tools that just answer the question and teach you the trap.

The calculators

Live now: RSU Tax & Cost Basis Calculator. Coming soon: ESPP, ISO/NSO + AMT, and Capital Gains (with W-8BEN for non-residents).

Not tax advice

Everything here is for education and illustration only — not financial, investment or tax advice. Your real tax depends on your full situation, income, state, residency and current law. Always verify with a qualified tax professional.

Is it free?

Yes, completely free. The site may be supported by ads.

Do I need an account?

No. There's no sign-up, nothing to install, and your inputs stay in your browser.

How can I contact you?

Email [email protected] with any question, correction or suggestion — corrections to tax logic are especially welcome.