Are the tools really free?
Yes. Every tool is completely free with no sign-up, account, or usage limit.
Is my data private?
Calculator inputs are processed in your browser and are not submitted to utilduck servers. Visit and device analytics, advertising requests, and browser-provided features are described separately in the Privacy and Cookie policies. There is no account or paywall.
How accurate are the results?
Tools use standard formulas and current references, and each page explains the method. Still, results are estimates for reference; consult a professional for important decisions.
Do I need to install anything?
No. Everything runs in your web browser on phone, tablet, or desktop.
What languages does utilduck support?
utilduck operates 11 locales: English, Korean, Japanese, Chinese, German, French, Spanish, Vietnamese, Indonesian, Portuguese, and Italian. Korea-specific tools and guides are Korean-only.
Can I use utilduck on a phone or tablet?
Yes. Every tool is built as a responsive web page that works the same way on phones, tablets, and desktops. There is nothing to download from an app store.
Does utilduck show ads?
Some pages display ads served through Google AdSense to help cover hosting costs. Ads never block the calculator itself, and you can manage ad personalization in your Google account settings.
How do I request a new tool?
Email biz7sean7claude7@gmail.com with the calculator or converter you would like to see. We read every suggestion, though we cannot guarantee a timeline for building it.
How do I report a calculation error?
biz7sean7claude7@gmail.com. For error reports, include the tool URL, browser, reproduction steps, and a changed example input where possible. Do not email names, government IDs, passport or account numbers, health information, or other personal or sensitive data.
Can I bookmark a tool or use it offline?
You can bookmark any tool page and it will load the same way each time. Offline use is not supported yet, since each page needs to load once from the server before it runs in your browser.