ODDLY LIKELY

Guess the odds.
Then see how wrong you were.

Free calculators and 45-second videos about the probability hiding in ordinary life — birthdays, queues, game shows, lottery tickets.

Try one now

A room holds a group of strangers. How many people do you need before there's a 50% chance two of them share a birthday?

Free games and calculators

Real or fake gameOne pattern is truly random, one was faked by a person. Coin flips, stars and dice: can you spot the real one? Birthday match calculatorSlide from 2 to 100 people and watch the odds of a shared birthday cross 50% at just 23. Three doors gamePlay the switch-or-stay puzzle, then run 1,000 rounds and watch switching win twice as often. Lottery odds calculatorPowerball, EuroMillions or your own rules — with the answer put next to everyday risks.

What this is

Oddly Likely takes one everyday moment a week and finds the real number behind it. You get a short video that makes you guess before it answers, and a page here where you can move the numbers yourself and check the arithmetic.

Every figure comes from a source you can click: a lottery operator, a weather service, a statistics agency. Nothing is rounded to make a better story. How the numbers are checked →

Watch

Short explainers, three times a week. Guess before the answer shows.

23 strangers, same birthday?

Switch or stay? Three doors

Lottery or lightning?

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