Decide who goes first
One flip settles it before a game or a match.
Coins 1
Coin Flip
Press Flip for an instant heads or tails. Flip up to 100 coins at once and watch a running tally build up, with the longest streak tracked alongside it.
How to use the coin flip
- Set how many coins. Leave it at 1 for a single flip, or flip up to 100 at once.
- Flip. Press the button or the Space bar. A single coin tumbles in the air for about five seconds before landing, so it feels like a real toss. Flipping several coins at once shows every result straight away.
- Watch the tally. Heads, tails and your longest streak build up as you keep flipping, until you press Reset.
How likely is a run of the same side
Each flip is independent, so a long run of heads or tails is rarer but not impossible. Here's the chance of a run at least this long, flipping one coin repeatedly.
| Run length | Chance |
|---|---|
| 2 in a row | 1 in 2 |
| 3 in a row | 1 in 4 |
| 5 in a row | 1 in 16 |
| 10 in a row | 1 in 512 |
These figures are for a run starting from any flip, not the chance across a whole session, which is higher the more you flip.
Worked examples
Common reasons people reach for a coin flip. Press "Load this example" to set it up.
Settle a tied vote
Two options, one flip, no argument.
Coins 1
A probability class demonstration
Flip 20 coins at once and compare the split to the expected 50/50.
Coins 20
Test how often long streaks appear
Flip 100 coins and check the tally's longest streak against the table above.
Coins 100
Tips for a fair flip
Announce the sides before you flip. If you're deciding something with someone else, agree who is heads and who is tails first, so the flip itself settles nothing but the outcome.
A streak doesn't mean the coin is due to change. Every flip is independent of the ones before it, so heads is exactly as likely after nine heads in a row as after any other run.
Screenshot the tally for a record. If you need proof of a fair result, the tally box shows the count and can be captured alongside the coin.
Why this flip is fair
Each flip is drawn from crypto.getRandomValues, the random source browsers use for encryption, so heads and tails each land with an exactly 50% chance. A real, hand-tossed coin has a small bias toward landing on the side it started on. A digital flip has no starting side, so it doesn't carry that bias.
Flips happen on your device and are never sent anywhere.
Coin flip questions
Is an online coin flip really 50/50?
Yes. Heads and tails each have exactly a 50% chance on every flip, with nothing carried over from earlier flips.
Is a real coin toss 50/50?
Not quite. A 2023 study of over 350,000 hand-tossed coins found a coin lands on the same side it started on about 51% of the time. A digital flip doesn't have that bias.
Why does the coin take a few seconds to land?
A single coin tumbles for about five seconds so the flip feels like a real toss instead of an instant answer. The result is decided the moment you press Flip, before the coin even starts moving, so the wait doesn't change the odds.
Can I flip more than one coin?
Yes. Flip up to 100 coins at once and see the heads and tails count straight away, with no five-second wait.
What does the tally show?
It keeps a running count of heads and tails for this visit, plus the longest streak. Reset it any time.
I got tails five times in a row. Is something wrong?
No. Five in a row happens about once in every 32 sets of five flips. Long streaks are a normal part of fair randomness.
Can I use this for a sports match or official decision?
It's fine for friendly games and everyday choices. For official matches, follow whatever method your league or competition rules require.
Can I flip a coin with the keyboard?
Yes. Press the Space bar to flip without reaching for the mouse.
Does it make a sound?
There's an optional flip sound that is off by default. Turn it on with the speaker button.