What is my connection type?
Where your browser supports it, the reading above is a coarse label for your connection quality, not a measurement of your line. Sites use it to decide whether to send the large image or the small one. A blank card means your browser refuses to say, which Firefox and desktop Safari both do on purpose.
What your browser reports about your network connection is shown above. Through the Network Information API, some browsers expose an effective connection type (like 4g or 3g), a rough downlink estimate in megabits per second, and whether you have data-saver turned on.
These values are deliberately coarse. The effective type buckets your real-world speed into slow-2g, 2g, 3g or 4g based on recent performance rather than the literal radio technology, so a fast home Wi-Fi connection typically reports 4g. It is a hint for adapting content, not a precise speed test.
Support is uneven. Chromium-based browsers expose the most detail, while Safari and Firefox expose little or nothing, so an empty value above simply means your browser chooses not to share it.
How a website reads this
This is the exact call a page makes. Nothing else is involved, and nothing is sent anywhere: the value is read in your browser and displayed to you.
navigator.connectionWhere supported, exposes effectiveType ("4g", "3g", "2g", "slow-2g"), downlink in Mbit/s and rtt in milliseconds. Firefox and Safari do not implement it on desktop, so the card is empty there, which is a privacy decision rather than a bug.
- Needs your permission
- No, it is read silently
- Can it be faked
- Partly. Not directly settable, but the values describe your current network, so connecting through something else changes them. Devtools network throttling changes them too.
- Contribution to a fingerprint
- About 1.5 bits, our own estimate. Our estimate. The coarse buckets carry little on their own, but downlink and rtt are noisy continuous values that change between visits, which makes them better for detecting a network than for recognising a person. How we estimate this.
What you should know
Why sites collect it
Sites use connection hints to adapt: sending smaller images on slow links, deferring heavy scripts, honouring data-saver, and pre-loading more aggressively on fast connections. It helps pages feel fast on poor networks.
Privacy implications
Connection type is a low-to-moderate signal. On its own it barely narrows you down, but a data-saver flag or an unusual speed class adds a little entropy to a fingerprint. It does not reveal your provider or location.
How to change or hide it
There is no user setting to spoof this directly, though turning data-saver on or off changes what is reported. Browsers that do not implement the API (Safari, Firefox) simply reveal nothing here, which is the most private option.
Frequently asked questions
Is this a speed test?
No. It reports a coarse effective connection class and a rough estimate the browser already has, not a fresh measurement. A real speed test transfers data to time it.
Why is my connection type blank?
Your browser probably does not implement the Network Information API. Safari and Firefox largely do not, so they report nothing here.
Sources
Browser behaviour changes and vendors cap these values differently, so the claims above that are not self-evident are checked against the specifications and vendor documentation below.
Last checked on . How these values are measured and estimated is set out on the methodology page.
Something wrong here? Tell us what your browser reports and it gets corrected.