US Tax Navigator for Korean F-1/J-1 Students: Fill Out 1040-NR and 8843 in Your Browser
Complete six guided steps to calculate your tax and fill official IRS PDFs. What you enter is never sent to a server.
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US Tax Navigator
For F-1/J-1 students from Korea who are in the United States. It calculates the 1040-NR, Form 8843, and selected state tax in six steps. It is not configured for residents of other treaty countries. Everything you enter stays in this browser.
The app interface is currently available in Korean.
Open the app →An immigration status alone does not determine which U.S. tax form a student should file. The first step is to determine tax residency by counting days of presence and any days that qualify for an exception. A student with a nonresident filing obligation will generally use Form 1040-NR. An F-1 or J-1 student who excludes days from the substantial presence test may also need to file Form 8843 even without income. I built this browser-based calculator to help with that first determination and the forms that may follow.
Calculate in six steps
The first step is residency. Enter your visa type, year of entry, and days present in each year, and the app first checks whether you are a nonresident alien (NRA) for tax purposes. Then enter your school scholarship (Form 1042-S), dividends, interest, stock gains and losses, deductions, and estimated payments, and the results step shows your federal 1040-NR tax and state tax together. If you choose a state with no income tax, such as Florida, it tells you no state return is needed, and if you choose Missouri, it calculates the MO-1040 tax.
Tax treaty and brokerage CSV support
If you select Korea as your country of residence for treaty purposes, the app suggests provisions that may apply. A treaty benefit is not determined by citizenship alone. It depends on treaty residence, the type of income, the purpose of the stay, and the requirements of the specific article. The app can separate potentially exempt and taxable amounts for income such as scholarships, but the user must verify the evidence and treaty provision before filing. For investment income, a Charles Schwab CSV can be sorted into dividends, interest, and trading gains and losses. Other brokerage data can be entered through a generic CSV format or by hand.
The results fill official IRS PDFs
In the last step, enter personal details such as your name and SSN, and the app fills calculated values into official IRS form PDFs for download. It supports Form 1040-NR with Schedules 1, A, NEC, and OI, as well as Form 8843. Items the app cannot determine are left blank, and the app lists what must be checked manually. The current preview uses 2025 forms. These PDFs cannot be filed for tax year 2026. First confirm that the IRS has published the 2026 forms and instructions and that the app has been updated to use them.
Everything you enter stays in this browser
This app is a static web app that runs without a server. Everything you enter, including your name, SSN, and income amounts, is stored only in this browser and never sent to a server. Tax calculation and PDF filling also run entirely in the browser, and uploaded CSV files are read directly by the browser. On a shared computer, clear the browser data when you finish.
A reference calculator, not tax advice
This app is a reference calculator and does not replace professional tax advice. It primarily supports F-1/J-1 students who are nonresidents for tax purposes. State-tax calculations are limited to Missouri, while the app only notes that Florida has no individual income-tax return. Do not file the generated result without further review if you are a resident for tax purposes or have self-employment income, cryptocurrency, income from several states, or another situation the app does not cover. Before filing, compare the result with IRS Publication 519, the Form 1040-NR instructions, and the official forms and instructions for the relevant tax year. Consult a tax professional when the facts are complex.