What is my browser language?
Above is the language list your browser hands to every site, in your order of preference. It is why a page can greet you in your own language before you log in. The list matters more than the first entry: an unusual ordering of two or three languages is a good deal more identifying than any single one.
Your preferred language, and the ordered list of languages your browser will accept, is shown above. Browsers send this as the Accept-Language header on every request and also expose it to JavaScript, so a site can greet you in the right language before you click anything.
The value is a locale code such as en-US (English as used in the United States) or nl-NL (Dutch as used in the Netherlands). The list is ordered by preference, so a site that does not have your first choice can fall back to your second.
You set this in your operating system or browser language settings, often without realising it doubles as a public signal. It is one of the quieter facts your browser volunteers to every page you open.
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.languagesAn ordered array of language tags, most preferred first, for example ["en-GB", "en", "nl"]. Falls back to navigator.language, a single tag, in browsers that withhold the list. The same preference travels as the Accept-Language header.
- Needs your permission
- No, it is read silently
- Can it be faked
- Yes. Set by your browser or system preferences, so changing it is a settings change rather than a hack. Firefox's resistFingerprinting reports en-US regardless of what you chose.
- Contribution to a fingerprint
- About 2.5 bits, our own estimate. Our estimate, and the reason it is not lower is the ordering: a single common language is cheap, but a specific ordered list of three or four is a much smaller crowd. How we estimate this.
What you should know
Why sites collect it
Sites use it to auto-select a language, format dates, numbers and currencies, and decide which regional content or store to show. It powers the "we noticed you might prefer X" banners.
Privacy implications
Language is moderately revealing. A common locale like en-US blends in, but an unusual combination or an uncommon secondary language can narrow you down, and it hints at your region and background. It is a standard input to fingerprinting scripts.
How to change or hide it
Change it in your browser or OS language settings. Privacy browsers may send a single, common value (often en-US) to all sites to reduce distinctiveness. Removing rare secondary languages from your list lowers your fingerprinting surface.
Frequently asked questions
Is my browser language the same as my location?
No. Language is your stated preference, not where you are. Someone in Japan can browse in English, and the two are detected separately.
Why does a site show the wrong language?
It may be using your IP-based country rather than your language list, or your first preferred language is one it does not support. This page shows exactly what your browser is announcing.
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.