How to flip a coin online
- Press Flip, tap the coin, or press the space bar.
- The coin spins in the air and lands on heads (H) or tails (T).
- The panel keeps count of heads, tails and your current streak.
Need several coins? Choose up to 10 under Number of coins. To see what happens over many flips, open Flip many coins at once and flip 10,000 in a split second.
Is this coin flip fair?
Yes. Each coin is decided by your browser's cryptographic random number generator (crypto.getRandomValues), so heads and tails each have exactly a 50% chance on every flip. Past flips do not affect the next one.
Flip 10,000 coins at once and you will see the share of heads land very close to 50%. The more flips, the closer it gets; over a handful of flips, streaks like five heads in a row are normal.
Are real coin flips 50/50?
Almost, but not quite. In a 2023 study, a team led by František Bartoš recorded 350,757 real coin flips by 48 people. Heads and tails came up equally often overall (50.0%), but a coin landed on the same side it started on 50.8% of the time, confirming a prediction from a physics model of coin tossing by Diaconis, Holmes and Montgomery. So if you can see which side is up before a real flip, calling that side gives you a tiny edge. An online flip has no starting side, so it has no such bias.
Source: Bartoš et al., Fair coins tend to land on the same side they started: Evidence from 350,757 flips, arXiv:2310.04153.
When people flip a coin
- Deciding who kicks off or who goes first in a game.
- Settling a two-way choice fast.
- Probability lessons: flip 100 coins and compare with 10,000.
- Any time there is no real coin in your pocket.
More than two options? Use the choice wheel or the yes or no wheel.
Questions
What is the chance of heads?
Exactly 50% on every flip. Each flip is independent, so a run of tails does not make heads more likely next time.
What are the odds of 5 heads in a row?
1 in 32 (0.5 multiplied by itself five times, about 3.1%). For 10 in a row it is 1 in 1,024.
Can I flip more than one coin?
Yes. Choose up to 10 coins, or flip 10, 100, 1,000 or 10,000 at once with Flip many coins at once.
Is anything stored?
No. The tally lives on this page only and resets when you leave.