Hijri Age Calculator – Calculate Islamic Calendar Age

A Hijri Age Calculator needs a named calendar standard. Hijri dates are not globally identical because calculated calendars and local crescent observations can assign different civil dates to the same numbered day.

This tool offers two explicit systems: the Umm al-Qura calculated calendar and the tabular Islamic civil calendar. You can enter a Gregorian or Hijri birth date, calculate age under the selected standard, convert the date, and find the next calculated Hijri birthday.

Select the Standard Before Entering the Date

Umm al-Qura is a calculated calendar used in Saudi official contexts. The Islamic civil option follows a fixed tabular pattern.

These standards can differ from each other and from locally observed months. Selecting the calendar first prevents an unlabeled “Hijri date” from appearing more universal than it is.

The chosen standard is repeated in the result.

Formula Used by the Hijri Age Calculator

After converting the birth and reference dates into the selected Hijri calendar, the tool calculates:

Years = reference Hijri year − birth Hijri year

Months = reference Hijri month − birth Hijri month

Days = reference Hijri day − birth Hijri day

If days are negative, one month is borrowed. The calculator checks the selected calendar’s actual previous month length and adds it to the day value.

If months are negative:

Months = months + 12

Years = years − 1

The result is therefore a completed Hijri age under the selected standard, not a Gregorian age multiplied by a constant.

Enter Gregorian or Hijri Birth Details

Choose Gregorian mode when the birth date comes from a civil record. The tool converts it to the selected Hijri calendar.

Choose Hijri mode when you know the Hijri year, month, and day. The supported Hijri years are 1317–1524, approximately corresponding to the tool’s Gregorian 1900–2100 range.

Impossible dates, future births, unsupported standards, and missing browser calendar data are rejected.

What the Result Compares

The main output gives Hijri years, months, and days under the selected standard. The detailed result also shows:

• Hijri birth date
• Equivalent Gregorian birth date
• Reference date in the Hijri calendar
• Gregorian chronological age
• Next calculated Hijri birthday
• Days until that birthday
• Selected calculation standard

Displaying Gregorian age separately shows that lunar-calendar age and solar-calendar age are not interchangeable.

Day 30 Birthdays

Hijri months can contain 29 or 30 days. A person born on day 30 may reach a target year in which the corresponding month ends on day 29 under the selected standard.

The calculator checks the next day to confirm that the month has ended. It then places the birthday on day 29 and labels the adjustment.

This is preferable to rolling the date invisibly into the following month.

Calculated Dates and Observed Dates

The elapsed number of civil days between two entered Gregorian dates is exact within date-only arithmetic. The Hijri year-month-day breakdown is exact only within the selected calculated calendar.

A local religious authority may begin a month according to crescent sighting, producing a date one day earlier or later. Religious observance should follow the applicable local guidance.

For another calendar tool where a boundary choice changes the result, see the Hebrew Birthday Calculator.

Useful Applications

Use the Hijri Age Calculator for calendar comparison, birthday planning, educational work, family records, and understanding why Hijri and Gregorian age totals differ.

It should not replace an official Saudi calendar, local religious determination, court record, immigration document, or civil registry.

By requiring a named standard and displaying observational limitations, the tool produces a result that is both useful and appropriately qualified.