Which date tool do you need?

Convert a date

Choose the date converter when a document gives a Hijri date and you need its Gregorian equivalent, or the other way around. Conversion changes the calendar label for a day; it does not calculate how long ago the day occurred. Note any Hijri adjustment when comparing results from different sources.

Calculate an age

Choose the age calculator when your starting point is a birth date and you want an age breakdown. Enter the calendar in which the birth date was recorded. Hijri and Gregorian years have different lengths, so their age numbers are not interchangeable for official eligibility rules.

Measure an interval

Choose date difference when you have two dates, such as the beginning and end of a project. Total days answer a different question from a years/months/days breakdown because calendar months have unequal lengths. Decide whether you need elapsed days or an inclusive count of dates before using the result.

A comparison example

Suppose a record lists a birth date in the Hijri calendar and a form asks for a Gregorian date of birth. First use conversion. If you also need the person's current age, use the age calculator with that birth date. If the form asks for time between two specific dates, use date difference rather than assuming the second date is today.

The guides below explain each tool with worked examples, limits and checks you can repeat. No account is required to read them or launch the tools.