Half birthday

Click here for Half birthday calculator

Half birthdady cake

You have just had a great party with many friends and even better, receive many gifts. The party is over. You have just finished celebrating! Cannot wait for another one? Haw about a half birthday? Have you heard about it?

It is a great reason to celebrate.

Half-birthday! It is a wonderful opportunity to celebrate twice a year. You can invite your friends, or just share your celebration using the web page Birthday Calculator.

There are a lot of calculators on the internet, but not all of them calculate in the same way as this one!

The easiest way to calculate your half birthday, is to add 6 months to the date of your birthday. For example, if you were born on July 25th, the your half birthday falls on January 25th. If you don´t want to calculate it yourself, just look at the table below!

Birthday Half Birthday
January 01 July 07
February 02 August 08
March 03 September 09
April 04 October 10
May 05 November 11
June 06 December 12
July 07 January 01
August 08 February 02
September 09 March 03
October 10 April 04
November 11 May 05
December 12 June 06


It is harder to look at the year as 365 days. However, it is better and more accurate. Most calculators use this method. 365 days in half is 182,5 days. This can be quite confusing!. If somebody was born in the morning they will celebrate their half birthday in a different day compared to somebody who was born on same day but in the afternoon. This is why on some calculators you have fill in  the hour you were born.

Half birthday Tropical yearAnother problem is, if that it is a leap year. Some calculators will calculate your half birth day using a different day, it depends if is leap year or not.

Birthdaycalculators.com will calculate slightly differently. Ti si based on a Tropical year (or Solar year) which is 365,2422 days long or 365 days, 5 hours, 48 minutes and 45 seconds. Half of that Tropical year is 182,6211 days. Rounded to 183 days.

Your half birth will be 183 days after you real birth day. It is easy, there is no problem with leap year or what time you were born.

Anyway, the most important thing is, that you have fun on your half birthday.