Are my financial numbers uploaded to a server?

No. CalcTools is 100% client-side. Every calculation — mortgage, loan, compound interest, tax — runs in your browser as plain JavaScript. There is no backend and no /api route. The site's Content-Security-Policy (connect-src 'self') even restricts which hosts the page may contact, so the privacy guarantee is enforced by the browser itself.

Are the calculations accurate?

Yes — each calculator uses the standard, published formula for its problem (the loan PMT formula, compound-interest future value, marginal tax bands, the HKMA stress-test rule, and so on). The verify suite hand-checks reference values against the implemented math before every build. Still, these are decision aids, not financial advice; confirm with a professional for a binding decision.

How is the currency converter's exchange rate sourced?

The converter ships with a build-time snapshot of exchange rates (taken from a public, no-key exchange-rate API at build time) bundled same-origin — it never makes a runtime request to any server in this MVP build. So currency conversion works offline and exposes no browsing data to a third party.

Do the Hong Kong calculators reflect the current year?

They use the published 2024/25 HK rates: Salaries Tax progressive bands (2%/6%/10%/14%/17%) and 15% standard rate with a $132,000 basic allowance; property Stamp Duty on the smoothed ad valorem band scale; MPF at 5% employee + 5% employer capped at the $30,000 monthly relevant-income limit. Always confirm the current figures on gov.hk before relying on a number for a real filing or purchase.

Does it work offline?

Yes. After the first load the app shell is cached, so every calculator works with no internet connection. Install CalcTools as a PWA and it opens and runs offline.

How is age calculated in years, months and days?

Age is counted in whole calendar years first, then whole months, then the remaining days. If the day of the month hasn't been reached yet, one month is borrowed and the actual length of that calendar month (28, 29, 30 or 31 days) is used — not a fixed 30-day month. That's why 31 January to 1 March is one month and one day in a non-leap year.

How many days old am I?

Enter your date of birth and read 'Age in total days' — the number of whole calendar days between your birth date and today, including leap days. The same figure is shown in weeks and hours for fun.

How does the calculator handle a February 29 (leap-day) birthday?

Your age in years counts to each February 29 in a leap year. In non-leap years the next-birthday countdown runs to February 28, the common convention, so the countdown is always finite.

Can I find my age on a specific past or future date?

Yes — change 'Age at this date' to any date. The calculator then shows your age on that day, not today. This is handy for forms that ask 'age on 1 September' or for historical ages.

Is my date of birth uploaded anywhere?

No. This age calculator runs entirely in your browser as plain JavaScript. There is no backend, no account and no analytics on your inputs — the date you type never leaves your device.

General

Age Calculator

Your exact age in years, months, and days from your date of birth — plus a next-birthday countdown.

Age Calculator

Enter your date of birth to get your exact age — the math runs live as you type.

Date of birthAge at this dateDefaults to today — change it to find your age on any date.

Your numbers never leave your device — all math runs in your browser.

Result

Your age

36 years 2 months 25 days

Age in total days13,235

Age in total weeks1,890

Age in total hours317,640

Next birthdayin 279 days

Turning37 (2027-06-15)

Age counts whole calendar years, then months, then days — leap years and Feb 29 birthdays included. Days-old figures use real calendar days, not 30-day months.

How to use this calculator

Enter your date of birth.
Leave 'age at this date' as today, or change it to check your age on any past or future date.
Read your exact age in years, months and days — plus your age in total days, weeks and hours, and the countdown to your next birthday.

Bookmark Age Calculator — it works offline once loaded. Figures are decision aids, not financial advice.