About Suikbang
Suikbang (suikbang.com) is an information tool that works out Korean tax, property and finance amounts. It currently runs 103 calculators, free and with no sign-up.
Suikbang is run by an individual.
Who writes it
One person reads the statutes, writes the formulas, builds the pages and reads the error reports. This is not a firm advising you as a licensed tax accountant or lawyer. It is the calculation written in the statute, moved into code. So what is offered as a reason to trust it is the process, not a licence.
Every calculator starts by reading the article on the National Law Information Center, in the original, even where the rate is already familiar. The figures in the article are worked through by hand once and checked against what the calculator returns before the page goes up. When the two disagree, the reading of the statute is doubted first, not the code.
107 statutory sources are wired to 326 places in the code, and 153 explainers work the same numbers through a second time. Amounts quoted in an explainer are checked by calling the calculator functions themselves. The arithmetic is never reimplemented for the check.
What catches the mistakes
Re-reading is not enough to stop a value going stale, so the checks run at build time.
- If an article cited on a page is not actually in the code, the build fails and nothing ships. That is what keeps the list of sources from becoming decoration.
- If an effective date has passed and the value has not changed, the build stops. Values are never switched automatically by date; the build tells a person it is time to change one.
- A separate check pulls the statute text again and compares it with the values in use. It is run before and after building a calculator.
- If a video states an effective date that differs from the list, the build stops. Dates do move. The tax on virtual assets was pushed back three times.
- Where a rule changed, the page carries both the date it was announced and the date it takes effect. An article number alone does not tell you what the figure is today.
- The English pages are not machine translated. If a number differs between the Korean and English version, the build stops. Explainers not yet translated are linked from the English list to the Korean page and marked as Korean.
What it covers
Only the points where the amount actually changes: the taxes paid when buying, holding and selling property; loan limits and repayments; the deadlines in a lease that cost money if missed; year-end tax settlement; filing for the self-employed; and investment returns. With an everyday category that checks whether an item is within a threshold a rule sets, they are grouped into eleven categories.
Where the numbers come from
Statutes and government announcements are the primary source. Each calculator names the provisions it reflects, and effective dates and amendment history are collected under Basis. Rules that have not taken effect are kept out of the working rates and listed under Upcoming. Government proposals that have not passed the National Assembly carry no legal force, so they sit separately under Tax reform and are never used in a calculation until enacted.
A map records which calculator has to change when a rule changes, and the build stops if that map drifts from the code. Numbers going quietly stale is the failure this site guards against hardest.
What it does not do
Suikbang does not give tax, legal or investment advice. The calculators reflect the main requirements only, results can differ with individual circumstances, and you should have a professional confirm before filing or signing. No financial product or property is recommended, and no return is guaranteed.
There is no sign-up and no login. Calculations run in your browser and the amounts you type are not stored. What is and is not collected is set out in the Privacy policy.
If something is wrong
If a calculation looks wrong, please tell us through Report an error. The screen and the values you entered are sent along, which makes it far quicker to reproduce. Citing the provision helps it get fixed faster.
Contact: hello@suikbang.com or Contact.
Our Shorts and lectures are published on the YouTube channel 수익방 (@suikbang), in Korean. The working that does not fit in a video is written out in Shorts, Explained.