JavaScript | Random
The Math.random() function is used to return a floating-point pseudo-random number between range [0,1) , 0 (inclusive) and 1 (exclusive). This random number can be scaled according to the desired range.
Syntax:
Math.random()
Example: This example uses Math.random() function to returns a random number.
<!DOCTYPE html><html> <body> <h2>Math.random()</h2> <p> Math.random() returns a random number between 0 and 1 </p> <p id="GFG"></p> <!-- Script to use Math.random() function --> <script> document.getElementById("GFG").innerHTML = Math.random(); </script></body> </html> |
Output:
Random Integers: The Math.random() method is used with Math.floor() function to return random integers.
Example:
<!DOCTYPE html><html> <body> <center> <p> Math.floor(Math.random() * 11) returns a random integer between 0 and 10 (inclusive): </p> <p id="demo"></p> </center> <!-- Script to use Math.random() function and Math.floor() function to return random integer --> <script> document.getElementById("demo").innerHTML = Math.floor(Math.random() * 11); </script></body> </html> |
Output:
Proper Random Function: JavaScript function always returns a random number between min and max where min is inclusive and max may be inclusive or exclusive both.
Example:
<!DOCTYPE html><html> <body> <p> When you click the button it will give a random value between 0 and 9 both inclusive: </p> <button onclick="document.getElementById('GFG').innerHTML = getRndInteger(0, 10)">Try it</button> <p id="GFG"></p> <!-- Script to return random number between 0 and 10 --> <script> function getRndInteger(min, max) { return Math.floor(Math.random() * (max - min)) + min; } </script></body> </html> |
Output on first click:
Output on second click:
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