Everyday Calculators
Calculators that do not belong to a single technical domain but come up regularly: how long between two dates, how many hours a shift ran, what mark is needed on a final exam, how much concrete a slab takes.
They use ordinary calendar and arithmetic rules, and each page states the convention it follows, since these are exactly the calculations where two reasonable methods can disagree.
Tools in Everyday Calculators
Age Calculator
Calculate your exact age in years, months, and days.
Date Calculator
Add or subtract days, or count the days between two dates.
Time Calculator
Add or subtract time values.
Hours Calculator
Calculate hours worked or time differences.
GPA Calculator
Calculate your semester and cumulative GPA.
Grade Calculator
Determine the grade needed on an exam.
Height Calculator
Convert height between centimetres and feet and inches.
Concrete Calculator
Estimate concrete volume for a slab, in cubic yards and bags.
Frequently asked questions
Do date calculations account for leap years?
Yes. Dates are handled with the browser's own calendar implementation, which applies leap years and month lengths correctly.
Which time zone is used?
Your device's local time zone. Calculations that span a daylight-saving change can therefore differ by an hour from a UTC-based calculation.