Is the coin flip truly random?

Yes. Where your browser supports it, the simulator uses crypto.getRandomValues — a cryptographically secure random source — to produce an unbiased 50/50 heads-or-tails result. It falls back to Math.random only if that API is unavailable.

What are the odds of heads or tails?

A fair coin has a 50% chance of heads and 50% chance of tails on every flip, independent of past results. Over many flips the running split converges toward 50/50 — a demonstration of the law of large numbers.

Can a coin land on heads many times in a row?

Yes. Streaks are normal and expected. The probability of any specific run of 10 heads is about 1 in 1,024, but with enough flips long streaks will appear. Each individual flip is still 50/50.

Does this coin flip send data anywhere?

No. The simulator runs entirely in your browser. No flips, results or counts are uploaded or stored on a server.

Coin Flip Simulator — Gera Tools

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The Coin Flip Simulator flips a fair virtual coin as many times as you like and tracks the running heads-versus-tails split. Use it to settle a decision, run a quick probability demo, or watch the law of large numbers pull the percentages toward 50/50.

Fair randomness

Each flip uses your browser’s cryptographically secure random generator (crypto.getRandomValues) where available, giving a genuinely unbiased 50% heads / 50% tails outcome. Every flip is independent — previous results never change the odds of the next one.

The law of large numbers

A single flip is unpredictable, but over many flips the proportion of heads settles close to 50%. Try flipping ×100 a few times: with 10 flips you might see 70% heads, but after 1,000 flips you will almost always be within a couple of percent of an even split. That convergence is the law of large numbers in action.

Everything runs locally in your browser, so no flips or counts are ever sent to a server.