Coin Flip
Flip one or many coins with animation.
What is this?
Coin Flip decides between two options — who goes first, heads or tails — at random. Flip 1 to 10 coins at once, each one spinning through a 3D flip animation before landing on Heads or Tails.
How to use it
Choose the number of coins and press Flip. Each coin spins several times before settling on its result. As the count grows, coins are arranged in a balanced grid so the layout never gets too tall.
Fair & private
Every result uses the browser's cryptographic random generator (crypto) with rejection sampling to remove modulo bias, giving heads and tails exactly a 50:50 chance. Nothing is ever sent to a server.
Why coin flips are fair — and how fair they really are
A tossed coin is fair because its landing face is extremely sensitive to tiny variations in launch angle, spin rate, and force, making it practically impossible for a person to control the outcome. That said, real-world research by physicist Persi Diaconis and others found that hand-tossed-and-caught coins land on the starting face slightly more often than 50% (roughly 51%) — a small bias from consistent tossing habits. That finding is about physical coin tosses and does not apply here, since this tool draws results with a cryptographic random generator.
Odds of 5 heads in a row — and the "gambler's fallacy"
For an independent event with 50% (0.5) odds each time, landing the same face 5 times in a row has probability 0.5 multiplied by itself 5 times: 0.5⁵ = 1/32 (3.125%). Ten in a row is 0.5¹⁰ = 1/1024, under 0.1%. But the 6th flip right after 5 heads is still exactly 50:50. Believing "tails is due" after a heads streak is the gambler's fallacy — a coin has no memory of past results, so the odds reset every single flip.