About

speed.cloudflare.com is a tool that allows you to measure the speed and consistency of your connection to the Internet. You can use it to verify that the speed your ISP promised you is the speed you are getting, compare different ISPs or test network connectivity in different parts of your house.

The measurements run on the Cloudflare network, which spans data centers in over 300+ cities worldwide. This ensures you are testing against a server that is close to you, which means you are measuring only the speed of your ISP, with minimal networks in between that may impact your score.

FAQs
Why build another speed test tool?

There are many speed test tools out there. Our mission is to help build a better Internet. To do so, we believe in giving users a choice of different services: you shouldn’t be tied to one provider and you should be able to compare results across different tools.

How did you build this tool?

When we started writing the first diagrams and writing the first lines of code, we wanted this project to get the most out of Cloudflare Workers. Today, the speed test tool is an edge application fully running on Cloudflare data centers in 300+ cities.

The public-facing static content (HTML, CSS, JavaScript, images) is stored in Workers KV. Yarn and Node compile everything and then we use an in-house tool to upload the generated files to KV. We handle dynamic requests in a Cloudflare Worker. It is composed of a lightweight http router to fetch the correct file from KV and a program providing the test files. Finally, the Worker is compiled with Wrangler, our open-sourced CLI, and webpack and uploaded to Cloudflare.

Building with Workers is no different than any other language. Everything is compatible with our CI pipeline, and we maintain different environments to avoid bugs to be released in production. Each environment involves different Workers and they are synchronized with specific Git branches.

We love to use our own products. We are hoping to create a great experience for you and countless others.

What are Cloudflare Workers and Workers KV?

Workers is a serverless application platform built on top of Cloudflare's network. When you publish a project to Cloudflare Workers, it's immediately distributed across 300+ cities around the world, meaning that regardless of where your users are located, your Workers application will be served from a nearby Cloudflare server, with extremely low latency.

Cloudflare Workers KV provides access to a secure low latency key-value store at all of Cloudflare's data centers in over 300 cities across 80 countries. Workers KV can be used in conjunction with Workers to build robust applications supporting dozens to millions of users.

Learn more and build your first worker today at workers.cloudflare.com!

How does it work?

The test uses the Cloudflare anycast network to test network performance. By leveraging the anycast network, the closest data center is found by network routing based off of BGP. This is a more accurate way of finding the closest data center than traditional methods, such as geo-location based off of your IP address.

Speed is measured by downloading/uploading progressively larger files and taking the 90th percentile speed. Ping is calculated by measuring the time it takes before your browser actually starts receiving data on a request, also commonly referred to in browsers as time to first byte. Jitter represents how stable your latency is: how big of a difference do we see between ping measurements? It's calculated as the average ping delta between any two consecutive measurements.

Will you sell the data you collect?

Cloudflare will never sell your data. Performance data is collected and anonymized and is governed by the terms of our Privacy Policy.

How can I improve my speed?

Your internet speed is dependent on a lot of factors. Speedcheck.org has a good overview of what affects your performance and what you can do to speed it up.

Why are my results different than other speed tests?

Many factors influence the speed that speed tests perform, including network conditions such as the peering arrangements that your ISP has and how that affects routing to Cloudflare's edge.

Another significant factor is the methodology used to calculate the result. While we cannot comment on the methodology others use to calculate speeds, we are completely transparent in which measurements we see and how that is used to calculate the result. Raw measurements can be downloaded after a test is performed and our worker implementation is open-source.

Why are all the data centers inside an airport?

Data centers are not physically located inside airports. They are generally located near airports and designated with IATA codes.

Cloudflare does not publish the addresses for data centers which is why the map uses the addresses of airports to show physical location.