Birthday Countdown

Give a birth month and day — no year — and see the next time that date occurs on or after today, how many calendar days remain, and the weekday. Leap-day birthdays wait for the next real 29 February instead of celebrating on the 28th.

How to use

Choose the birth month and the day of the month. 31 April and other impossible dates are rejected.
Read days remaining, the next birthday’s calendar date, and its weekday. Zero means the birthday is today.
If the date has already passed this year, the next occurrence is next year (or the next leap year for 29 February).
Use Age if you need years-months-days from a full birth date. This page never computes age.

How it works

A countdown does not need a birth year. The question is only “when is the next 25 December” or “when is the next 29 February,” measured from this browser’s local civil date. If today is that month and day, remaining days is 0 and the next birthday date is today — the cake is now, not in 365 days.

Once the date has passed, the search moves to next year. 26 December looking for 25 December lands on 25 December next year. The day count is elapsed midnights, the same idea as Days Between Dates, so 1 December to 25 December is 24 days, not an inclusive tally of both dates.

Leap-day birthdays are the exception people argue about. This page does not move 29 February to 28 February or 1 March. It waits until the next year that actually has a 29 February. After 1 March 2023, the next 29 February is 29 February 2024. That is the opposite of the Age calculator, which treats 28 February as the anniversary in a common year when stacking years-months-days. Both rules are used in real life; they are labelled differently on purpose.

Impossible days such as 31 April cannot occur in any year and return no result. 31 November is the same. 29 February is valid only in leap years; the search simply skips common years until it finds one, within a short window of upcoming years.

The tool does not send reminders, does not know time zones other than the browser’s calendar date, and does not add clock time. For “how old will they be on that birthday,” enter the full birth date and that target on the Age page.

Formula

Next birthday = first valid month/day on or after today
Days remaining = next birthday − today (calendar days)

Worked examples

Birthday still ahead this year
25 December, from 1 December 2024 → 24 days, Wednesday 25 December 2024
Leap-day birthday after 1 March 2023
29 February, from 1 March 2023 → 29 February 2024

Useful notes

Today is taken from this browser’s local calendar date.
29 February uses the next real leap day, not 28 February — unlike the Age anniversary clamp.
No birth year is required, so this page does not compute age.

FAQ

What if today is the birthday?: Days remaining is 0. The next birthday date is today.
What if someone was born on 29 February?: The countdown targets the next 29 February in a leap year. It does not move the date to 28 February or 1 March.
Do I need to enter a birth year?: No. Only month and day are used, so the tool does not compute age.
Why is this different from the Age calculator on leap day?: Age clamps a 29 February birthday to 28 February in common years when stacking years and months. This countdown waits for the next actual 29 February.
Is the day count inclusive of today?: No. It is elapsed calendar days until the next birthday. If the birthday is tomorrow, remaining days is 1. If it is today, remaining days is 0.

Related tools

See all Date & Time tools.