How To Generate Random Number In Ruby

Generating random numbers is a common task in programming. In Ruby, there are several ways to generate random numbers, and in this blog post, we will discuss the most common methods and how to use them effectively.

Using the rand Method

The simplest way to generate a random number in Ruby is by using the rand method, which returns a random float between 0 (inclusive) and 1 (exclusive). Here’s an example:

puts rand

If you want to generate a random number within a specific range, you can provide an argument to the rand method. The argument can either be an integer or a range. When you provide an integer n, it generates a random number between 0 (inclusive) and n (exclusive).

# Generate a random number between 0 and 9 (inclusive)
puts rand(10)

If you provide a range as an argument, the rand method generates a random number within that range (inclusive).

# Generate a random number between 5 and 10 (inclusive)
puts rand(5..10)

Using the Random Class

Ruby also provides a Random class that allows for more advanced use-cases and better control over the random number generation process.

To generate a random number using the Random class, you can use the Random.rand method in a similar way as the global rand method:

# Generate a random number between 0 and 9 (inclusive)
puts Random.rand(10)

You can also create an instance of the Random class and call the rand method on it. This is useful when you want to have multiple random number generators with different seeds or if you want to have better control over the randomization process.

# Create a new random number generator with a specific seed
random_generator =

# Generate a random number between 0 and 9 (inclusive)
puts random_generator.rand(10)


In this blog post, we learned how to generate random numbers in Ruby using the rand method and the Random class. These methods provide an easy way to generate random numbers within specific ranges or with a specific seed, making them a powerful tool for various programming tasks.