Calculate numbers

Enter a price to instantly see the amount before tax, the tax, and the total. Japan’s 10% and 8% rates are built in, or use any rate.

Pick a date of birth to see the exact age, days until the next birthday, days lived and the Chinese zodiac sign, with an age chart by birth year.

Instantly get the date and weekday N days or N business days after or before any date. Weekends and holidays can be skipped too.

Work out hours worked from start, end and break times, and add them up. Also adds and subtracts time and converts to decimal hours.

Enter the total and the number of people to see what each person owes. Round to an easy amount, have some people pay more, and let the organizer cover the difference.

Instantly convert Unix time (epoch seconds or milliseconds) to a UTC, local or Japan time date, and a date back to Unix time.

Instantly count how many days are left until a date, or how many days are between two dates. Include the start day, or count weekdays only.

Work out X% of a number, what percent one number is of another, percent change, and the original number before a discount.

Convert between Western years and Japanese era years (Reiwa, Heisei, Showa, Taisho, Meiji) from a year or a date of birth. With zodiac animal, age, and a quick reference table.

Pick a date and instantly see what day of the week it is — plus the nth weekday of the month, day of the year, week number and the same date in other years.

Choose a country, convert between hourly, monthly and annual pay, and estimate your take-home pay after tax and social contributions, with a breakdown.

Enter your height and weight to instantly see your BMI, its category, and your ideal weight (BMI 22).

Convert between tsubo, square meters (m²), tatami (jo), ares, hectares, square feet and acres all at once. You can also work it out from a room’s length × width.

Turn seconds into hours, minutes and seconds, or 1.5 hours into minutes. Converts seconds, minutes, hours, days, weeks and milliseconds.

Convert color codes between HEX, RGB, HSL, HSV, OKLCH and CMYK. You can also check the contrast ratio (WCAG) between text and background.