Rozna Calc

Everyday calculators: age, dates, percentages, units.

Rozna Calc (rozana means daily) is a set of the small calculations that come up every week: how old someone is on a given date, how many days until an exam, what 15% off comes to, how a percentage change is worked out. Each page gives the answer with the method written underneath, so it is also a quick way to check your own arithmetic.

The pages are written for India: dates in day-month-year, numbers in lakh and crore where that helps, and examples from school marks, shopping and exam forms rather than from American tax returns.

Everything runs in your browser. Nothing you type is sent anywhere, and there is no account.

Tools

• Age calculatorExact age in years, months and days on any date, total days lived, the weekday you were born, and days to the next birthday.
• BMI calculator (kg and cm, or feet and pounds)Body mass index from your weight and height, the WHO category it falls in, and the weight range that would put you in the normal band, with the formula shown.
• Date calculator: days between dates, add or subtract daysDays, weeks and working days between two dates, the date a number of days before or after a date, and the weekday of any date, with leap years handled.
• Percentage calculatorWhat is X% of Y, what percent X is of Y, the percentage change between two numbers, and a price after a discount, with the method shown.

Who makes this

Rozna Calc is written and kept by ABSU Mobilities, Hyderabad. Every tool page says how it calculates, shows a worked example, and lists its sources with the date they were read. If a number looks wrong, tell us.