Coin Flip

How to use

1. 1Pick a mode. Single flip animates one coin and keeps a session history. Multi flip runs a batch and shows full stats. Custom outcomes replaces heads and tails with two labels you choose.
2. 2In Single flip mode, click Flip the coin to animate a fresh result. The heads and tails counts and percentages update beneath the coin so you can watch the distribution.
3. 3In Multi flip mode, set the number of flips (from 1 up to 10,000), or tap a preset (1, 10, 100, 1,000, 10,000), then click Flip to generate the batch.
4. 4Read the result panel: total flips, heads count and percentage, tails count and percentage, longest heads streak, and longest tails streak. The full H / T sequence is shown beneath the stats.
5. 5In Custom outcomes mode, type your two options (or pick a preset like Yes / No or Pizza / Tacos) and click Decide for me. The fair 50/50 flip picks one for you.
6. 6Use the Copy buttons to grab the decision, the sequence, or a summary report. Reset history or Clear result starts the session fresh.

About this tool

Coin Flip is a fair virtual coin that uses crypto.getRandomValues for genuine 50/50 outcomes; a real physical coin is actually slightly biased toward the side it started on (about 51 percent, per the 2007 Diaconis study), so this simulator is more fair than a real flip for any binary decision. Three modes cover the situations people actually search for. Single flip animates a single coin and records a session history so you can watch the heads and tails counts develop in real time. Multi flip runs up to 10,000 independent flips in a single batch and surfaces the full H / T sequence, the running heads and tails counts and percentages, and the longest observed heads streak and longest tails streak (useful for probability homework, classroom demonstrations of the Law of Large Numbers, and as a quick sanity check that the percentages converge toward 50 percent as N grows). Custom outcomes swaps the heads and tails faces for any two short labels (Yes/No, Stay/Go, Pizza/Tacos, Option A/Option B, Buy/Sell), turning the same fair flip into a one-click decision maker for indecisive moments without changing the underlying probability. Every flip uses unbiased rejection sampling on top of the Web Crypto random source, so each outcome is independent of every previous outcome (there is no streak debt, gambler's fallacy correction, or hidden seed). Copy buttons grab the current decision, the full H / T sequence, or a complete summary report (counts, percentages, streaks, sequence) ready for a homework writeup, a Slack message, a probability lab notebook, or a classroom whiteboard. Useful for picking who goes first in a game, breaking a tie between two restaurant options, settling a friendly bet, modeling Bernoulli trials in a statistics class, generating reproducible-feeling but fair coin sequences for a teaching demo, and any situation where a fair, fast binary outcome matters. Flips, history, labels, and statistics all stay on your device; nothing is uploaded or logged.

Free to use. Works in your browser. No signup, no login.