About Tooldeb

Tooldeb is a collection of calculators and converters you can use straight from the browser — no sign-up, nothing to install. 185 of them are available in English across 15 fields. Korean is the site's primary language; tools that only make sense inside Korea are published in Korean only.

What we build

The goal is not one more copy of a calculator that already exists, but tools whose numbers actually hold up in the place they are used. Money is shown in the units people read it in, and country-specific tools are not force-translated just to fill a page.

Every calculation finishes on your own device. The numbers you type are never sent to a server and never stored. The site ships as static files, so there is no calculation server to send them to in the first place.

Who builds it

One person, not a company or a team. There is no office and no phone line, and the only way to reach us is the email address below. That is stated up front on purpose: when you decide how far to trust a result, knowing who produced it is the first thing you need.

Where the numbers come from

For physics, mathematics, and unit conversion — anything with a fixed definition — we use the standard formula unchanged. The formula used is printed on each tool page so you can check the result by hand.

For tools whose values come from statute — taxes, social insurance — we do not rely on secondary write-ups or memory. The source text is pulled from the Korean Ministry of Government Legislation open API, compared article by article, and the article number is left in a source-code comment. The older tools are not all there yet: where a formula or a rate has been fixed for decades — severance pay, VAT — some files still carry the constant alone, with no article number. There are 15 such files, and the deploy check pins that list path by path: if a file not on the list arrives without an article number, or if the list changes at all, the check fails. So the exception set does not grow. Rates that change yearly live as a single constant so an amendment is a one-line fix.

Every calculation has tests with expected values worked out by hand, including the boundaries — zero, negatives, a zero denominator. Inputs that make no sense return nothing rather than a plausible number: a calculator that answers confidently for a negative floor area is a wrong-answer generator, not a tool.

It can still be wrong

Results here are for reference. Laws are amended, and real filings and contracts carry exceptions, deductions, and special cases this site does not model. For anything where an amount becomes binding — tax, payroll, contracts — confirm it with the responsible authority or a qualified professional. The limits of our responsibility are set out in the Terms and Disclaimer.

If a number looks wrong, tell us. Which tool, what you entered, and what it returned is enough to reproduce it. How to get in touch · hello@tooldeb.com