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Coin Flip

H
Ready to flip
Total Flips
0
Heads
0 (0%)
Tails
0 (0%)
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Enter values to see the worked formula.

What Your Result Means

How This Calculator Works

Each flip calls JavaScript's Math.random() to generate a number between 0 and 1. Values below 0.5 are heads, the rest are tails — giving each side an equal 50% probability. The tool tracks cumulative totals and computes running percentages by dividing each outcome's count by the total number of flips.

Quick Questions

Is this coin flip truly fair?

Yes. It uses the browser's built-in pseudorandom number generator (Math.random), which produces a uniform distribution. Each flip has an independent 50/50 chance regardless of previous results.

Why don't I see exactly 50/50 after many flips?

Small deviations are normal and expected with any random process. The law of large numbers says the ratio converges toward 50% as flips increase, but it doesn't guarantee exact equality at any finite point.

Can I use this for serious decision-making?

It's fine for casual tie-breaking. For decisions with significant consequences, consider weighing pros and cons rather than relying on randomness.

Does the animation affect the result?

No. The result is determined instantly by the random number generator. The 0.6-second spin animation is purely visual — the outcome is decided before the animation completes.

Sources

Method & review

MethodologyHow we calculate this Reviewed & Updated2026-04 Next review2027-04

Estimate only. Results reflect your inputs and standard formulas. Double-check important decisions independently.