Two friends want the same seat, two teams must pick who serves first and nobody has a coin in their pocket. You need something quick that both can see and nobody suspects is rigged.
How to use Coin Flip step by step
1. Press "Flip coin"
The coin spins for a moment and stops on heads or tails.
2. Read the result
You will see the side that came up, the history of the last 20 flips and the tally with percentages.
3. Repeat or flip in bulk
×10 and ×100 toss several coins at once and summarise how many landed on each side.
The Step Count: Traditional Friction vs. KorexTools
Deciding with a real coin
- Find a coin.
- Agree which side is which option before flipping.
- Flip and hope nobody argues about the spin or the bounce.
With KorexTools Coin Flip
- Agree who is heads and who is tails.
- Press the button.
- The result stays visible to everyone.
Heads or tails: why a virtual coin can be fairer than a real one
Flipping a coin is the oldest way to settle a tie: who goes first, who pays for coffee, which team picks the side. It works because it offers two outcomes with equal probability and nobody can argue with it.
A physical coin is not perfect: a study by mathematicians Diaconis, Holmes and Montgomery (2007) showed it lands on the same side it started on in about 51% of flips. This tool uses the browser's cryptographic randomness and splits 50/50 in the long run, regardless of how you toss it.
What you can do here
- •Flip one coin to choose between two options.
- •Toss 10 or 100 coins at once to see the real split.
- •Follow the running count of heads and tails with percentages.
- •Check the history of the last 20 flips.
Real probabilities
| Situation | Probability | What it means |
|---|---|---|
| One heads in a single flip | 50% | Each side has an equal chance |
| Two heads in a row | 25% | One in four pairs |
| Exactly 50 heads in 100 flips | ≈ 8% | Some deviation is normal |
| A run of 5 heads in a row | ≈ 3% | For a given start, but it happens in long runs |
Common Mistakes and How to Avoid Them
- ⚠️Believing it is "due" tails after a run of heads.
- ⚠️Switching from "best of three" to "best of five" when the result is unwelcome.
Frequently Asked Questions
Is the virtual coin truly random?
Yes. It uses the browser's cryptographic generator (crypto.getRandomValues), which gives heads and tails exactly the same probability.
Why do I get streaks of the same side?
It is normal. In 100 flips, runs of 5 or 6 identical results are common. Each flip is independent and does not "make up" for the previous one.
Is it suitable for an official draw?
It works for everyday decisions and games. For a prize draw or one with legal requirements, use the method the rules demand and a witness.
Why is 10 flips not exactly 5-5?
With few flips that is expected. The split approaches 50% the more you flip, but it almost never lands exactly even.
What I would do if I were in your shoes
«One trick we use: flip the coin and notice which side you were hoping for. If the result disappoints you, you already know what you really wanted to pick.» — DataKorex Engineering Team