Below Script sends GET request once. It creates a single Virtual User(VU) and sends the get request.

import http from 'k6/http';
import { check } from 'k6';

export default function () {
  // Target URL
  let res = http.get('https://httpbin.test.k6.io/get');

  // Basic check to ensure status is 200
  check(res, {
    'status is 200': (r) => r.status === 200,
  });

  // Print response body to console
  //console.log(res.body);
}

k6 run test.js

To make the same script run for a duration. In this case the number of iterations varies based on how fast the request is completed based on keeping user constant 1(VU).

k6 run test.js --duration 5s

To make the same script run for a iteration. In this case the number of iterations would be 5 and VU is 1.

k6 run test.js --iterations 5

Below Script sends GET request and sleeps for 1 second. So if we run the test for 5 seconds then we run 4 request by same user

import http from 'k6/http';
import { check } from 'k6';
import { sleep } from 'k6';

export default function () {
  // Target URL
  let res = http.get('https://httpbin.test.k6.io/get');
  sleep(1);

  // Basic check to ensure status is 200
  check(res, {
    'status is 200': (r) => r.status === 200,
  });

  // Print response body to console
  //console.log(res.body);
}

To make the same script run for a 10 iteration and 10 VUs.

k6 run test.js -i 10 -u 10

Instead of supplying in command argument we can do the same thing by defining in constant as below

import http from 'k6/http';
import { check } from 'k6';

export const options = {
  vus: 10,          // fixed number of VUs
  iterations: 10  // each VU loops for 30 seconds
};

export default function () {
  let res = http.get('https://httpbin.test.k6.io/get');


  check(res, {
    'status is 200': (r) => r.status === 200,
  });

  //console.log(res.body);
}