Coin Toss
Flip a coin and randomly decide heads or tails
Features
Decide heads or tails with one button
Press to randomly determine heads or tails
Spinning animation and sound effects
Toggle coin spin landing animation and sound on/off
Automatic history and ratio tracking
Counts and ratios of heads and tails displayed automatically to one decimal place
No registration needed, works entirely in browser
Processing done only in browser without sending results
How to Use
Choose animation and sound effects
Toggle spin animation and sound effects on/off with switches
Flip the coin
Tap the "Flip Coin" button to execute the toss
Check the result
After the animation, confirm heads or tails displayed below the coin
View history and tallies
Continue flipping to see the history sequence and heads/tails count and ratio
Reset the record
Clear all records by tapping "Reset History and Tallies" after confirming
Use Cases
Deciding first or second
Fairly determine order before games or sports with random chance
Making binary decisions
Use as a tiebreaker when torn between two equally appealing options
Learning and verifying probability
Flip repeatedly and observe how heads/tails ratio approaches 50/50
Lottery via screen sharing
Share your screen during a video call and confirm results with everyone
Basic Knowledge
Is coin toss probability really 50/50?
The basic assumption is that heads and tails each have a probability of 1/2 (50%) in a coin toss. However, since each result is independent, the number of heads and tails may not be equal in a small number of flips.
- Law of Large Numbers：A principle stating that as the same trial is repeated, the actual ratio observed approaches the theoretical probability (50%).
- Independent Trials：Trials where the previous result does not affect the probability of the next outcome. Even after 5 heads in a row, the probability of heads on the next flip remains 50%.
Coin Toss in Sports
Coin tosses are used in many sports as a method to decide which team gets the right to choose first before the match begins.
- Soccer：Before the match starts, the referee flips a coin, and the team that correctly guesses chooses either the field to attack or who kicks off.
- American Football：The team that wins the coin toss chooses whether to attack first, play defense, or select which sideline to start on.
- Tennis：The winner of the coin toss or racket spin chooses serve, receive, or court side.
Safety and Privacy
Runs entirely in your browser
Your input data is processed only within your browser and is never sent externally.
Processing only in your browser
Toss results and history is processed entirely within your browser, and input data is not sent to any server.
Communications encrypted with HTTPS
Page loading is also encrypted by TLS, and content cannot be read by third parties.
No transmission to third parties
Input content is not sent to external services such as ad networks or trackers.
No automatic saving of results
Toss results and input suggestions are not stored on the server.
Updates
- update #224
Add Coin Toss
Press the button and the coin spins to randomly determine heads or tails. Toss history and counts and ratios of heads and tails are automatically tallied.