cURL to k6 Load Test — Convert a Real Request into a Performance Suite

2026-07-17 · By Avinash K

The fastest path from "I want to load-test this endpoint" to "here is a passing k6 script running in CI" is capture a real cURL, convert to k6, add thresholds. Here is the full workflow.

Open the target request in Chrome DevTools → Network → right-click → Copy → Copy as cURL. Paste into the cURL → Code Converter and pick "k6" as the target.

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

export const options = {
  vus: 20,
  duration: '2m',
  thresholds: {
    http_req_failed: ['rate<0.01'],
    http_req_duration: ['p(95)<800'],
  },
};

export default function () {
  const res = http.post('https://api.example.com/orders',
    JSON.stringify({ productId: 42, qty: 2 }),
    { headers: { 'Content-Type': 'application/json',
                 'Authorization': `Bearer ${__ENV.API_TOKEN}` } });
  check(res, { 'status is 201': (r) => r.status === 201 });
  sleep(1);
}

export const options = {
  stages: [
    { duration: '30s', target: 10 },
    { duration: '2m',  target: 50 },
    { duration: '30s', target: 0 },
  ],
};

k6 run --out json=result.json script.js
k6 run --out influxdb=http://localhost:8086/k6 script.js

k6 exits non-zero when thresholds fail. Add it as a GitHub Actions step and PR checks fail automatically when p95 regresses.