Birthday Calculator

This birthday calculator counts the days until your next birthday. Enter your date of birth and you'll see the date, its weekday, the age you're turning, your half-birthday, the day of the week you were born and your next five birthdays.

Calculation and content reviewed by EZ Calculators Editorial Team on October 5, 2026.

Enter values

Build the scenario below, then calculate for a complete result report.

Runs in your browser

ReferenceToday locally or another date

CountdownDST-safe calendar days

Planning viewFive annual anniversaries

Set the birthday record

A name is optional and only labels this browser result. Use the complete birth date so current age and every turning age can be checked.

Recorded date

Name

Date of birth

Choose the countdown viewpoint

Count from defaults to today's date in this browser. Change it to plan ahead or reproduce what the countdown showed on another calendar date.

Next includes today

Count from

Calendar planning, not an official age ruling

The result uses date-only Gregorian arithmetic. It does not infer a birth time, live time-zone countdown, legal age rule, school cutoff, benefit date, or other program-specific convention.

How many days until my birthday?

Count the calendar days from today to this year's birthday, or next year's if it has passed. Born December 10, 1995 and counting from October 5, 2026, your next birthday is Thursday, December 10, 2026. That's 66 days away, or 9 weeks and 3 days, and you'll turn 31.

How to use the birthday calculator

Enter a full date of birth, year included. The year lets the calculator tell you the age you're turning. The count starts from today, but you can pick any other start date to plan ahead.

A name is optional and only labels the result. On your birthday itself, the countdown says Today instead of jumping to next year.

Add a name if you want one on the result.
Enter the date of birth.
Keep today's date in Count from, or choose another day.
For a February 29 birthday, pick February 28 or March 1 for common years.
Press Find next birthday and read the countdown, the weekday and the timeline.

Birthday countdown examples

These come straight from the calculator. The countdown counts days passed, so the start date itself isn't counted. July 1 to July 15 is 14 days.

Days until the next birthday
Date of birth	Count from	Days left	Next birthday	Turning
December 10, 1995	October 5, 2026	66	Thursday, December 10, 2026	31
October 20, 1990	October 5, 2026	15	Tuesday, October 20, 2026	36
July 15, 2010	July 1, 2026	14	Wednesday, July 15, 2026	16
February 29, 2000 (Feb 28 rule)	February 28, 2026	Today	Saturday, February 28, 2026	26
February 29, 2000 (Mar 1 rule)	February 28, 2026	1	Sunday, March 1, 2026	26

What day was I born?

The results list the weekday of your birth date. December 10, 1995 was a Sunday, and October 20, 1990 was a Saturday.

You'll also see the weekday of your next birthday. It usually moves forward one day each year and two days after a February 29 sneaks in, which is why it pays to read each date instead of guessing the pattern.

Your next five birthdays

The timeline lists the next five birthdays with the age, date, weekday and days away. It's handy for spotting a birthday that lands on a weekend for a party, or a milestone age you want to plan for early.

The results also show the next round-number birthday. For a December 10, 1995 birth, that's turning 40 on Monday, December 10, 2035.

Next five birthdays for December 10, 1995, counted from October 5, 2026
Age	Date	Weekday	Days away
31	December 10, 2026	Thursday	66
32	December 10, 2027	Friday	431
33	December 10, 2028	Sunday	797
34	December 10, 2029	Monday	1,162
35	December 10, 2030	Tuesday	1,527

How the half-birthday is worked out

Your half-birthday here is six calendar months after a birthday, not 182 or 183 days. December 10 gives June 10. If the target month is too short, it moves to that month's last day.

For the December 10, 1995 example, the next half-birthday is Thursday, June 10, 2027, when the person is 31 and a half.

February 29 birthdays

If you were born on a leap day, most years don't have your date. Pick whether you celebrate on February 28 or March 1 and the calculator sticks with that choice for the countdown, your age and every date in the timeline.

In a leap year like 2028, the timeline uses February 29 itself. For official age rules, check what the school, employer or agency uses.

Sources

These references cover the calendar and leap-year rules used for birthday dates.

U.S. Naval Observatory: introduction to calendarsHow the Gregorian calendar organizes days, months and years.U.S. Naval Observatory: leap yearsThe rule for which years include February 29.NIST: leap day and the Gregorian calendarBackground on February 29 and why the calendar needs it.IETF RFC 5545: iCalendarThe standard behind recurring all-day dates in calendar apps.

FAQ

Does the birthday countdown include today?

No. It counts days from today to the birthday, so tomorrow is 1 day away. On the birthday itself the result says Today rather than counting to next year.

How old will I be on my next birthday?

The result shows the age you're turning. It needs your full birth year, because a month and day alone can't tell how many birthdays you've had.

What day of the week is my birthday this year?

The calculator shows the weekday of your next birthday, plus the weekdays for the four after it. December 10 falls on a Thursday in 2026 and a Friday in 2027.

Can I count down from a date other than today?

Yes. Change Count from to any date on or after the birth date. The countdown, age, half-birthday and five-birthday timeline all update from that day.

When is my half-birthday?

Six calendar months after your birthday. A July 15 birthday has a January 15 half-birthday. If the month is too short, the calculator uses that month's last day.

Why do two birthday countdowns sometimes differ by a day?

One may count both today and the birthday, or use a different time zone or leap-day rule. This one counts calendar days from the start date and doesn't count the start date itself.

Is my birth date saved anywhere?

No account is needed and the math runs in your browser. The name field is optional and only labels the result on your own screen.