About Util Monster

All tools are provided completely free. No registration or login required.

Intuitive and clean interface that anyone can use easily.

Continuously adds new features and improvements based on user feedback.

Supports various languages including Korean, English, Japanese, and Chinese.

Most calculators and converters process inputs in the browser. Features that need network data, such as WHOIS or other APIs, send the minimum request needed; analytics and advertising services may also use cookies or network requests.

Rules and rates can change. Higher-risk tools show methodology, official sources, effective dates, limitations, and a last-review date where available. Results remain estimates unless explicitly identified as official.

Util Monster is an independently operated online tool service. It is not a government agency, regulator, lender, medical provider, or standards body. The site does not claim professional review unless a page names the reviewer and scope.

For rules, rates, and standards we prefer legislation, regulators, standards bodies, and first-party documentation. A reviewed tool states its method, assumptions, limits, source, effective date, and actual review date; dates do not advance automatically during a build.

Send the page URL, language, inputs, actual result, expected result, and supporting source to help@util.monster. We reproduce the issue, correct code or content when supported, and update the displayed review record when a substantive review is completed.