How to flip a coin online
- Tap the coin or press Flip a coin. The coin spins and lands on heads or tails.
- Need a lot of flips? Use Flip 10 or Flip 100 to toss many coins at once and see the totals instantly.
- The counters show how many heads and tails you have thrown, the percentages and the longest streak in a row. The history line lists your last 60 results.
- Share the result with a card or link if you are settling a bet with someone who is not in the room.
Is this coin flip really 50/50?
Yes. Each flip uses your browser's cryptographically secure random number generator (crypto.getRandomValues), the same source used to create encryption keys. Every flip is independent and has exactly a 50% chance of heads, with no pattern, no memory of previous flips and no way for the page to favour one side. A real coin is actually slightly less fair: studies of physical tosses found a small bias towards the side that was facing up at the start.
Streaks surprise people. In 100 fair flips, a run of six or seven of the same side in a row is completely normal, and the split is rarely exactly 50/50; something between 40 and 60 heads is expected. Try Flip 100 a few times to see this for yourself, which makes it a handy classroom demonstration of probability and the law of large numbers.
Everything runs in your browser and nothing is recorded.
What are the odds of heads?
Exactly 1 in 2, or 50%, on every flip, no matter what came before.
What are the chances of getting 10 heads in a row?
1 in 1,024 (0.5 to the power of 10), about 0.1%. Over many thousands of flips it will eventually happen.
Can I use this to make decisions?
Yes, that is what most people use it for. A fun trick: if you feel disappointed by the result, you have learned what you really wanted.