Simple script for benchmarking using Node and prime numbers.

prime-tester.js

const isPrime = (n) => {
	let max = Math.floor(Math.sqrt(n));

	for (var i = 2; i <= max; i++) {
		if (n % i == 0) {
			return false;
		}
	}

	return true;
};

const testSize = (size) => {
	let numbers = [];

	let startTime = (new Date()).valueOf();

	for (var i = 2; i < size; i++) {
		if (isPrime(i)) {
			numbers.push(i);
		}
	}

	let endTime = (new Date()).valueOf();
	let timeElapsed = endTime - startTime;

	console.log(`Took ${timeElapsed > 1000 ? timeElapsed / 1000 : timeElapsed } ${timeElapsed > 1000 ? 'seconds' : 'milliseconds' } to find ${numbers.length} prime numbers from a set of ${size} numbers.`);
};

testSize(10);
testSize(100);
testSize(1000);
testSize(10000);
testSize(100000);
testSize(1000000);
testSize(10000000);