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Free tools and guides for founders outside the US
Calculators, checkers and plain-English guides to help you plan your US company, tax ID and yearly filings before you spend anything.
Plan with real numbers
Tax Calculator
Estimate 2026 US federal tax for an individual, a non-resident or a C-Corporation.
CalculateLLC State Filing Calculator
Formation and yearly report fees for all 50 states and DC, side by side.
Compare statesITIN Eligibility Check
Answer three questions to see if an ITIN fits your situation and what to prepare.
Check nowUS Business Records Guide
What records your US company should keep, and for how long.
Read the guidePerks
Current Ze Filing offers and free extras for clients.
See perksDownload our guides
ITIN Guide (free PDF)
A step-by-step playbook for what to do after your ITIN arrives: US address and phone, ITIN-friendly credit cards, online accounts, payment processors, US investing and the key 2027 tax dates.
DownloadSeller Guide (free PDF)
The non-US seller’s playbook to forming a US LLC, getting paid in dollars, handling sales tax and staying compliant every year.
DownloadGood to know
- Our tools give general estimates, not tax or legal advice.
- Government fees and tax figures change. We last checked them in October 2026 and confirm them again before we file anything for you.
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