JavaScript Math Random method returns a random number (floating) between 0 (inclusive), and 1 (exclusive). To get the integer number you have to use Math.floor() function with it.
Example: How to use Math.random()
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<!DOCTYPE html> <html> <body> <p id="result"></p> <script> document.getElementById("result").innerHTML = Math.random(); </script> </body> </html> |
Output:
Q: How to Generate Random Whole Numbers with JavaScript?
Answer: It’s easy and useful to generate random decimals or whole numbers. See below steps to do get the whole number:-
- Use
Math.random()to generate a random decimal. - Multiply that random decimal by 100 or any number.
- Use another function,
Math.floor()to round the number down to its nearest whole number.
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Math.floor(Math.random() * 100); |
Complete Example and Programming code:-
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<!DOCTYPE html> <html> <body> <p id="result"></p> <script> function randomWholeNum() { // Only change code below this line. return Math.floor(Math.random() * 100); } document.getElementById("result").innerHTML = randomWholeNum(); </script> </body> </html> |
How to return random integers between the given range?
Answer: See below code for Returns a random integer from.
0 to 9
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Math.floor(Math.random() * 10); |
0 to 10
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Math.floor(Math.random() * 11); |
0 to 100
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Math.floor(Math.random() * 101); |
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Math.floor(Math.random() * 101); |
10 to 100
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<!DOCTYPE html> <html> <body> <p id="result"></p> <script> function randomWholeNum() { var min=10; var max=100; var random = Math.floor(Math.random() * (+max - +min)) + +min; return random; } document.getElementById("result").innerHTML = randomWholeNum(); </script> </body> </html> |
Supported Browsers: The browsers supported by JavaScript Math.random() function are listed below:
- Google Chrome
- Internet Explorer
- Firefox
- Opera
- Safari
Do comment if you have any doubts and suggestions on this tutorial.
Note: The All JS Examples codes are tested on the Safari browser (Version 12.0.2) and Chrome.
OS: macOS 10.14 Mojave
Code: HTML 5 Version
Degree in Computer Science and Engineer: App Developer and has multiple Programming languages experience. Enthusiasm for technology & like learning technical.