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I often have to generate random prime numbers so I created this simple utility that does it for me. It lets you generate as many random primes as you need from the given range. It works in the browser and is powered by alien technology from the future.

## Random Prime Generator Options

Random Prime Range
Count and Separator
Random Primes Base

## Random Prime Generator Examples (click to try!)

Ten Random Primes
This example generates ten random prime numbers, from the range starting at 2 and ending at 100.
```23
7
19
97
79
53
59
3
89
29```
Generate this many random prime numbers.
Starting value.
Ending value.
Use this symbol to separate output values.
Decimal Base
Seven-digit Prime Numbers
In this example, we create a random list of 20 seven-digit primes, separated by a comma. The search range starts with a million and ends at two million.
`1453369, 1438169, 1770679, 1450103, 1767397, 1156171, 1306597, 1950449, 1842941, 1662553, 1637521, 1018177, 1569181, 1924547, 1978589, 1543429, 1396103, 1247527, 1811647, 1798631`
Generate this many random prime numbers.
Starting value.
Ending value.
Use this symbol to separate output values.
Decimal Base
Random Binary Primes
In this example, we set the output base to binary (base 2) and generate six random binary primes from the range 2 to 50.
```10111
101111
10
11
11111
10001```
Generate this many random prime numbers.
Starting value.
Ending value.
Use this symbol to separate output values.
Binary Base

## How Does This Random Prime Generator Work?

This random prime number generator works entirely in your browser and is written in JavaScript. First, it generates a list of possible prime values starting from `start` and ending with `end` (range values specified in options). These are all numbers that are not divisible by 2 or 3. Then, it uses the `Math.random()` function to select random values from this list and calls the `isPrime()` function to check whether this number is actually a prime. It repeats this process until the output list has as many primes as you specified in the `count` option. Finally, it uses the `join()` function to separate all randomly selected primes by the specified `separator` character in options.

### Created by Browserling

This random prime generator was created by me and my team at Browserling. Behind the scenes, it's actually powered by our web developer tools that are used by millions of people every month. Browserling itself is an online cross-browser testing service powered by alien technology. Check it out!

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