Heads or Tails
Heads or tails is the call you make before a coin flip: heads is the side with the portrait or emblem, tails is the other side, and each has a 50% chance.
Heads or tails each come up 50% of the time on a fair coin, and no call is more likely to win than the other.
Flip heads or tails now
What's your call?
Practice · not recorded · no coins
How to play heads or tails
Heads or tails takes two people and one coin. One person calls heads or tails, ideally while the coin is still in the air, then the coin is flipped and caught or allowed to land. If the side facing up matches the call, the caller gets the choice; if not, the other person does. Agree before the flip on what each side decides, for example heads means you pick the movie. With no coin in your pocket, tap the flip above and you get heads or tails right away. If one flip feels too sudden, play best of 3: the first side to land twice takes it.
Should you call heads or tails?
It makes no difference whether you call heads or tails. A fair coin gives each side a 50% chance, and in the largest hand flip study so far, 350,757 flips by Bartoš and colleagues in 2023, heads and tails each came out at 50.0%. The one effect they measured is that a coin lands on the side it started on 50.8% of the time, so the starting side matters a little and the call itself does not. Online, even that effect is gone. Call whichever side you like. If you want to know which side of a real coin counts as heads, see our guide to heads and tails on different coins.
Heads or tails with friends and the Global Flip
To play heads or tails with a friend far away, open a private room in the FlipACoin app and share the 6 character code or invite link. You both watch the same coin flip live and see the result at the same moment. Pick a single flip, best of 3 or best of 5, or play against a bot when nobody is around; bots are always marked Bot. For a bigger crowd, the Global Flip lets players everywhere call heads or tails on the same coin every few minutes, and the hourly Big Flip is the biggest round of all. Coins in the app are virtual and have no cash value.
Same side k times in a row
| k | Specific side (e.g. heads) | Any side, counted from the first flip |
|---|---|---|
| 2 | 1 in 4 (25%) | 1 in 2 |
| 3 | 1 in 8 (12.5%) | 1 in 4 |
| 5 | 1 in 32 (3.13%) | 1 in 16 |
| 10 | 1 in 1,024 (0.098%) | 1 in 512 |
| 15 | 1 in 32,768 | 1 in 16,384 |
| 20 | 1 in 1,048,576 | 1 in 524,288 |
FAQ
What does heads or tails mean?
Heads or tails is the call you make before a coin flip. Heads is the obverse, the side that usually shows a portrait or emblem, and tails is the reverse. One person calls a side, the coin is flipped, and whoever matches the side facing up gets the choice. On a fair coin each call has a 50% chance, so heads or tails is a simple and fair way to settle a choice between two people.
Is heads or tails more likely?
Neither. In the largest coin-flip experiment to date, with 350,757 hand flips, heads came up 50.0% of the time (95% interval 49.8% to 50.2%), so there was no heads-or-tails bias. The starting side was what mattered: coins landed the same way up they started 50.8% of the time. If nobody sees which side starts up, heads and tails are equally likely.
Which side of a coin is heads?
Heads is the obverse, the front of the coin, which usually shows a portrait, a head of state or a national emblem. Tails is the reverse, which usually shows the value or another design. The US Mint uses exactly these definitions. On coins without a portrait, the side with the country's name or coat of arms is normally treated as heads.
Why is tossing a coin considered fair?
A properly tossed coin gives both sides an equal chance, and neither person controls the outcome. The coin turns over many times in the air, so tiny differences in the flick decide the result. Statisticians Andrew Gelman and Deborah Nolan showed that even a weighted coin can't be meaningfully biased when it is flipped and caught. That is why referees use a coin toss to start football and cricket matches.