Skip to main content
miji.be
miji.be

Language

English日本語中文Español

Site

HTTP/3

The latest version of HTTP, running on the QUIC protocol. It eliminates TCP head-of-line blocking and speeds up redirect responses.

Oct 31, 2026 / About 1 min read

Redirect

HTTP/3 is the third major version of HTTP, standardized by the IETF in 2022 as RFC 9114. While the earlier HTTP/1.1 and HTTP/2 run on TCP, HTTP/3 uses QUIC (RFC 9000 / standardized in 2021), which runs on UDP, as its transport. For this reason, the head-of-line blocking that occurred at the TCP layer does not happen.

In URL shorteners, the payload of a redirect response (301/302) is extremely small, so the overhead of establishing the connection becomes relatively large. Where QUIC's 0-RTT resumption is available, requests can be sent without waiting for the handshake to complete, which saves the round trips spent on establishing the connection. However, because data sent with 0-RTT carries a replay risk, RFC 8470 allows this sending only for safe methods such as GET and prohibits sending unsafe methods through this path. Requests asking for a redirect are GET, so they fall within this condition.

QUIC has the following characteristics: (1) because connection multiplexing is independent per stream, the impact of packet loss is localized, (2) connection migration (keeping a connection alive when the IP address changes) improves stability in mobile environments, and (3) because encryption with TLS 1.3 is a prerequisite, there is no option to communicate in plain text.

As of 2024, all major browsers (Chrome, Firefox, Safari, Edge) support HTTP/3, and CDNs such as Cloudflare, Fastly, and AWS CloudFront also support HTTP/3. When a URL shortener serves redirects through a CDN, HTTP/3 support can often be enabled with only a configuration change.

Was this article helpful?

Related Terms

HTTP/2

The successor protocol to HTTP/1.1. Dramatically improves web page loading speed through multiplexing, header compression, and server push.

HTTPS

The secure version of HTTP that encrypts data transmitted between a browser and a web server using TLS.

TTFB

The time from when a browser sends a request to when it receives the first byte of the response. A fundamental metric for server responsiveness.

CDN

A network of geographically distributed servers that deliver web content from the location nearest to the user. Improves speed and reliability.

Redirect Latency

The delay incurred during a shortened URL's redirect process. A critical performance metric that directly affects user experience and conversion rates.

SSL/TLS

Cryptographic protocols that provide secure communication over the internet by encrypting data between client and server.

Related Articles

How Redirect Chains Impact Web Performance - Speed Optimization for Short URLs

Quantitative analysis of how short URL redirect chains affect Core Web Vitals and page load speed. Covers redirect hop optimization, edge redirects, and HTTP status code selection for maximum performance.

How URL Shorteners Work - The Technical Side of Redirects

Discover the technical mechanics behind URL shortening: hash generation, database lookups, HTTP redirects, and more. Includes HTTP response examples and base-62 encoding calculations.

What Happens When You Click a Link? A Peek Behind the 0.5-Second Curtain

What happens behind the scenes when you click a link? An adventure-style guide covering DNS, requests, responses, and how URL shortener redirects work.

Put the terms to work

Shorten a URL for Free