As promised, CloudFlare delivered HTTP/3 this week. If you don’t know what this is and what it could mean for web browsing in the future I highly recommend reading their blog and other sites about it. HTTP/3 brings another fundamental shift to transport protocols by building on the lessons learned from TCP and UDP. I’m particularly intrigued to see HTTP requests begin before the handshake is complete. CloudFlare released it to their customers who signed up to enable it early. The option will roll out to everyone else later. I was one of those that signed up for the early test. This was the email I received:

Hi there,

I’m a product manager at Cloudflare. You’re receiving this email because some time ago you placed on an early access waitlist for QUIC support.

We’re excited to share that now has access to Cloudflare’s QUIC and HTTP/3 (the version of HTTP built on QUIC) features.

You can now go ahead and turn HTTP/3 on in the Network tab of the Cloudflare dashboard. will be one of the first sites on the Internet to support HTTP/3 requests. Congratulations!

The Cloudflare edge supports the draft version of the IETF QUIC and HTTP/3 standards. You can read more about HTTP/3 (including how to configure clients like Google Chrome and curl to use it) on our blog.

Happy HTTP/3’ing :)

Upon receiving this I QUICly (sorry, couldn’t resist the pun) headed out to my site and enabled it. Unfortunately, I can’t upgrade my Chrome browser at this time and my first attempt at using their curl instructions failed. As such, I will have to come back and update this post with some packet capture and performance detail. Fortunately, they did provide some screen shots a starting data, so for now read CloudFlare’s post I linked above and search the web for more info.