---
title: "HTTP/2 | Grafana k6 documentation"
description: "When you make HTTP requests in k6 it will automatically upgrade the connection to HTTP/2.0 if the server supports it, just like your web browser would."
---

> For a curated documentation index, see [llms.txt](/llms.txt). For the complete documentation index, see [llms-full.txt](/llms-full.txt).

# HTTP/2

## Overview

HTTP/2.0 is the latest version of the HTTP protocol. It improves significantly upon HTTP/1. Most importantly, it introduces a binary wire protocol with multiplexed streams over a single TCP connection. This solves a long-standing performance issue with HTTP/1.1: [head-of-line blocking](https://en.wikipedia.org/wiki/Head-of-line_blocking).

Well, it at least *partially* solves it. The TCP congestion control mechanisms can interfere with the intended independent nature of the multiplexed streams in cases of lost/dropped packets and retransmission/reassembly. The full solution is to run HTTP/2.0 over UDP, as Google implemented with [QUIC](https://en.wikipedia.org/wiki/QUIC).

## Additional features of HTTP/2.0

- Builtin compression of HTTP headers
- Server push
- Pipelining of requests
- Prioritization of requests

## Load testing HTTP/2 with k6

When you make HTTP requests in k6, k6 automatically upgrades the connection to HTTP/2.0 if the server supports it, just like your web browser would.

To check what protocol was used for a particular request, refer to the `proto` property of the response object.

JavaScript ![Copy code to clipboard](/media/images/icons/icon-copy-small-2.svg) Copy

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

export default function () {
  const res = http.get('https://quickpizza.grafana.com');
  check(res, {
    'protocol is HTTP/2': (r) => r.proto === 'HTTP/2.0',
  });
  sleep(1);
}
```

To see the values that the `r.proto` field can have, refer to the documentation for [k6 HTTP](/docs/k6/next/javascript-api/k6-http/response/).