What Data Does Cloudflare Collect When You Use Its Speed Test?

When you run the Speed Test at speed.cloudflare.com, Cloudflare receives your IP address, an estimate of your location at the country and city level, and the Autonomous System Number (ASN) of your ISP. Cloudflare truncates the IP address it receives to /24 for IPv4 and /48 for IPv6, and it shares anonymized measurement information with measurement partners — but not your IP address. This applies to anyone who starts a test on the site; the page states that your IP address will be shared with Cloudflare and processed under its privacy policy when you run the test.

What Cloudflare receives

The Speed Test page lists three pieces of information Cloudflare receives as part of the test:

• Your IP address — the address you use to connect to the Speed Test service.
• An estimate of your location — at the country and city levels.
• The Autonomous System Number (ASN) of your ISP — the identifier for the network your connection belongs to.

Cloudflare uses the IP address to estimate your geolocation and to identify the ASN associated with it.

How your IP address is handled

Cloudflare truncates the IP address it receives as part of your use of the Speed Test:

Truncation means the stored form of the address no longer identifies a single device. A /24 IPv4 block covers 256 addresses, and a /48 IPv6 block covers a much larger range, so the truncated value points to a network segment rather than to you specifically.

What is shared with measurement partners

Cloudflare shares anonymized measurement information with its measurement partners as part of its contribution to a shared Internet performance database. According to the page, this includes things like:

• The estimated geolocation
• The ASN associated with your Speed Test

The page states explicitly that Cloudflare does not share your IP address with its measurement partners.

What the test measures and what it costs you in data

The test reports download, upload, latency, jitter, and packet loss, and produces a Network Quality Score with pending scores for streaming, gaming, and video calls. One practical data point from the page: a speed test can consume up to 200MB of data. That matters if you are on a metered mobile connection or a capped plan — running repeated tests adds up.

What this means in practice

• If you are uncomfortable with your IP address reaching Cloudflare at all, note that the test cannot run without it — the page says your IP address will be shared with Cloudflare when you run the test.
• If your concern is third parties, the page's stated position is that partners receive anonymized measurement data and never your IP address.
• If your concern is data usage, budget for up to 200MB per test.

For the full wording, see Cloudflare's privacy policy, linked from the Speed Test page.