About Coin Flip Simulator

Flip a fair coin N times — tallies + raw sequence. Optional seed.. Part of the DevTools Surf developer suite. Browse more tools in the Fun / Niche collection.

Use Cases

• Demonstrate probability distributions in a classroom
• Generate reproducible random binary sequences with a seed
• Settle a decision with a verifiable neutral flip
• Audit a random-number generator's fairness with a visible sequence

Tips

• Deterministic when you pass a seed — reproducible for demos
• Tallies include the raw H/T sequence so you can verify fairness
• Use count=10000 to check the law of large numbers in action

Fun Facts

• A 2007 Stanford study found real coin flips aren't actually 50/50 — they're biased ~51% toward the starting face because of the flip's rotation.
• The longest recorded streak of consecutive heads in a fair coin flip experiment is 36, achieved by statistician Karl Pearson's assistant in 1900 after 24,000 flips.
• Cryptographically secure random number generators (CSPRNGs) produce better randomness than physical coin flips — real coins have manufacturing imperfections that introduce bias.

FAQ

Is the randomness fair?

Yes — crypto.getRandomValues gives true 50/50 flips. More random than a physical coin (real coins have slight bias from manufacturing).

Can I use a seed?

Yes — provide any seed and the sequence is reproducible. Useful for demos and deterministic tests.

What's the tally for?

Shows heads vs tails count plus the raw sequence. Useful for illustrating the law of large numbers — flip 10,000 times and see the ratio approach 50/50.

Why would anyone flip N times?

Probability class demos, hobby simulations, or settling disputes where 'one flip' feels too arbitrary. N=5 with majority rule is a more stable decision.