Birthday Calculator

How it works

The birthday calculator takes your date of birth and works out your next birthday from today. It counts the days until that date, tells you which day of the week it lands on, and — if you tick the option — shows your zodiac sign based on your birth month and day.

The countdown rolls forward to the next occurrence automatically: if your birthday this year has already passed, the tool counts toward the one next year. The zodiac mapping is the standard Western twelve-sign calendar and is offered as a bit of fun, not as astrology or advice.

Knowing the weekday helps with planning. If your birthday falls on a Saturday next year, you already know the celebration will not clash with a workday. The weekday is computed from the calendar directly, so it is correct for any year, including leap years when 29 February shifts everything after it by a day.

Examples

Example: born 15 June

On 11 August 2026 the next 15 June is in 2027, so the calculator shows the days until that date and the weekday it falls on (and, with the option on, the Gemini sign for a 15 June birth date).

Example: born 29 February

For a leap-day birth date the calculator uses 1 March in non-leap years as the next occurrence, so the countdown is to 1 March, and the weekday shown is for that date. This matches how most diaries and calendars handle 29 February birthdays.

FAQ

How many days until my birthday?

The tool finds the next occurrence of your birth month and day from today and counts the midnights to it. If your birthday this year has passed, it counts toward next year’s date automatically.

What zodiac sign am I?

With the option enabled, the calculator maps your birth month and day to the standard Western zodiac sign (for example 15 June is Gemini). This is provided for fun and is not astrology or personal advice.

What day of the week is my next birthday?

The tool reports the weekday of the next occurrence of your birth month and day. Because leap years shift the calendar, the weekday can change from year to year — for example a birthday on 15 June may fall on a Monday one year and a Tuesday the next after a leap day.

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