When a decision is a genuine toss-up, a coin flip is the fairest way to settle it — and this one never rolls under the couch. Tap the coin for a single animated flip, or flip 10, 100 or 1,000 coins at once to see how heads and tails balance out over time. The tape keeps a running count, the current streak and the longest runs of each side.
How to use the coin flipper
- Tap the coin, or press Flip, for one animated toss. Use the keyboard by tabbing to the button and pressing Enter or Space.
- Press Flip 10, Flip 100 or Flip 1,000 to add many flips instantly.
- Watch the tape: total flips, heads and tails with percentages, the current streak and the longest heads and tails runs.
- The strip under the coin shows the last 60 flips, newest first. Press Reset to start a new tally.
Coin flip probability
Each flip is an independent event with two equally likely outcomes:
| Run of the same side | Probability (for that exact run) |
|---|---|
| 2 in a row | 1 in 4 (25%) |
| 3 in a row | 1 in 8 (12.5%) |
| 5 in a row | 1 in 32 (3.1%) |
| 7 in a row | 1 in 128 (0.78%) |
| 10 in a row | 1 in 1,024 (0.098%) |
Those odds are for a run starting at a particular flip. Over a long session there are many places a run can start, so streaks appear far more often than the table suggests on its own.
Streaks are normal
In a computer simulation of 100,000 sets of 100 fair flips, the longest run of one side averaged about 7. Some set of 100 flips contained a run of 6 or more about 81% of the time, and 7 or more about 54% of the time. When people invent “random” sequences by hand, they rarely include runs longer than four — one simple way researchers can tell real coin flips from made-up ones.
How close to 50% should the results be?
The proportion of heads drifts toward one half as flips accumulate (the law of large numbers), but the raw count can wander. For n flips the number of heads has
Worked example: 100 flips
- Expected heads: 100 ÷ 2 = 50.
- Standard deviation: √100 ÷ 2 = 5 heads.
- The exact chance of landing between 40 and 60 heads is 96.5%, so 43 or 57 heads is unremarkable, while 30 heads would be a real surprise.
Flip 1,000 coins and the standard deviation grows to about 15.8 heads, but as a share of all flips it shrinks to 1.6 percentage points, which is why the percentage on the tape settles near 50%.
Fair ways to use a coin
- Call it before the flip. Decide who takes heads before the coin is tossed.
- Use one flip per decision. Don’t switch to “best of three” after an unwelcome result.
- Unequal choices: to pick one of three options fairly, flip twice and assign HH, HT and TH, re-flipping on TT; or use the random number generator.
- A coin flip as a tie-breaker works best when both sides truly are acceptable — if you feel relief or disappointment at the result, that tells you what you really wanted.
For more than two outcomes, roll the dice roller or draw from the random name picker. To turn a probability into betting odds, see the odds calculator.
The virtual coin is fair by construction; real coins can show tiny physical biases. Nothing you flip here is stored after you leave the page.
Frequently asked questions
Is the virtual coin really 50/50?
Yes. Each flip uses one unbiased random bit from your browser's cryptographic generator, so heads and tails each have a probability of exactly one half, independent of every earlier flip.
What are the odds of getting heads five times in a row?
1 in 32, or about 3.1%, because each flip has a ½ chance: ½ × ½ × ½ × ½ × ½ = 1/32. Ten heads in a row is 1 in 1,024.
After several tails, is heads more likely?
No. Believing a result is 'due' is the gambler's fallacy. A coin has no memory, so the next flip is 50/50 no matter what came before.
How long a streak should I expect in 100 flips?
The longest run of the same side in 100 flips averages about 7. A run of at least 6 happens in roughly 4 out of 5 sets of 100 flips, so long streaks are normal.
Are real coin tosses fair?
Very nearly, but not perfectly. A 2023 experiment with more than 350,000 hand-tossed flips found coins landed on the side they started on about 50.8% of the time. The virtual coin has no such bias.