When is your Multibirthday?

Multibirthday

Your shared birthday

Add up everyone's ages — whenever the sum is a round number, it's Multibirthday! Two people celebrate two Multibirthdays per year, three people celebrate three, and so on.

↓ Calculate now

Also available as app — free for iOS & Android

Who do you want to calculate with?

Choose a preset — fields will be pre-filled.

Enter birthdays

Enter first names and birthdays — we'll calculate your next Multibirthdays.

Celebrity Examples

Click on a group to load their birthdays

↑ Click to fill the calculator automatically

Also available as app

Multibirthday with you everywhere — free for iOS and Android

Download on the App Store Get it on Google Play

have Multibirthday

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