Random Numbers

JavaScript FAQ | JavaScript Numbers FAQ  

Question: How do I generate random numbers in JavaScript?

Answer: To generate random floating-point numbers in the range from 0 to 1, use the Math.random() method:

num = Math.random()  // num is random, from 0 to 1 
If you need random floating-point numbers in the range from A to B (A<B), use this code:
num = A + (B-A)*Math.random()  // num is random, from A to B 
For a random integer in the range from M to N (where M and N are two integers, M < N) use:
num = Math.floor(M + (1+N-M)*Math.random())  // num is random integer from M to N 

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