Dice and Coins
Coin Flip
Coin flip is a tool for tossing a fair virtual coin. Flip once to settle a decision, or flip many times to see the split.
1 flip.
How the coin flip works
Press flip and the coin lands heads or tails with exactly equal chance, drawn from your browser cryptographic random source. Flip one coin for a decision, or set the count and flip up to a thousand at once with the heads and tails split shown. The running tally keeps score across presses until you reset it.
Is a real coin flip actually 50 50
Curiously, a real coin toss is not quite fair. A physics model by Diaconis, Holmes and Montgomery predicted in 2007 that a flipped coin wobbles enough to land on the same side it started about 51 percent of the time. In 2023 a team led by Frantisek Bartos put it to the test with 350,757 real flips and measured exactly that bias: coins landed on the starting side 50.8 percent of the time. Small as it sounds, betting one dollar a flip across a thousand flips against someone exploiting it would cost about 19 dollars on average.
This virtual coin has no starting side and no wobble, so it is one of the few coin flips that is truly 50 50. When a real toss must be fair, the study's own advice applies: keep the starting side hidden from the person calling.
Streaks are normal
A fair coin produces runs that look suspicious but are pure chance. Each specific streak halves in probability with every extra flip.
| Run of the same side | Chance |
|---|---|
| 3 in a row | 12.5% |
| 5 in a row | 3.1% |
| 7 in a row | 0.78% |
| 10 in a row | 0.10% |
Across 100 flips the longest streak is typically around seven, which is why the roller reports the longest run whenever you flip in bulk. Seeing six heads in a row is not evidence of a broken coin, it is evidence of a working one.
Settling things fairly
Best of three or best of five changes nothing about fairness, each flip stays an even chance, but it does smooth out bad luck for the loser of a single toss. For decisions with more than two options, the random number picker spins across any range, and the dice roller covers one in six and beyond.
Frequently asked questions
Is the coin fair
Yes. Each flip is an independent draw from the browser cryptographic source with heads and tails exactly equally likely, which is fairer than a physical toss.
Can I flip many coins at once
Yes, up to 1000 in one press, with the heads and tails split, the running tally and the longest run shown.
Why did I get several heads in a row
Streaks are expected from a fair coin. Five in a row has about a 3 percent chance on any given run, and across many flips such runs are routine.
Does the previous flip affect the next one
No. Each flip is independent, so the coin is never due for heads or tails, whatever just happened.
Related pickers and draws
- Random Number Picker Wheel
- Number Wheel Spinner
- Classroom Number Picker
- Random Playing Card Generator
- Raffle Number Generator
- Random Ticket Number Generator
- Random Group Assignment Generator
Prefer a plain number? Use the random number generator.