User-Agent is a string sent by the browser in HTTP requests and exposed via JavaScript. It usually includes browser, engine, operating system and historical compatibility tokens.
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See browser, system, language, timezone and exposed capabilities
Every web page has access to a set of information the browser exposes via JavaScript, without asking permission: the navigator object carries the User-Agent, the preferred language (navigator.language) and the language list; Intl.DateTimeFormat reports the time zone; and existence tests on APIs reveal support for cookies, localStorage, Service Worker, WebGL, WebAssembly and clipboard. This data helps debug compatibility and understand why a feature works on one device and not another. The flip side is that, aggressively combined, many of these signals increase browser uniqueness and feed fingerprinting. This tool shows only common, transparent information, reads everything locally and does not collect canvas, audio, installed fonts or invasive combinations, nothing is sent to analytics.
Nothing here comes from a server: each field is read from an API the browser itself provides. The User-Agent, platform and languages come from the navigator object; the time zone comes from Intl.DateTimeFormat().resolvedOptions().timeZone; connectivity from navigator.onLine. That is why the results describe exactly the environment of the tab you are in.
The 'capabilities' use feature detection: instead of guessing from the browser name, the tool checks whether the feature actually exists, whether 'serviceWorker' is in navigator, whether localStorage responds, whether a WebGL context can be created, whether WebAssembly is defined, whether the Clipboard API is present. It is the same technique robust apps use to decide which features to enable.
A string like 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/… Safari/537.36' looks confusing, but it is historical: the tokens 'Mozilla', 'AppleWebKit', 'KHTML, like Gecko' and 'Safari' exist for compatibility with old sites, not because you are running all those browsers. What matters is the pair of system (Windows NT 10.0; Win64; x64) and the real engine/version (Chrome/…).
Precisely because it is ambiguous and heavy, the User-Agent is being gradually replaced by User-Agent Client Hints in Chromium browsers: structured, more controlled fields (brand, version, platform, mobile) that the site requests explicitly, reducing the passive exposure of device details.
In isolation, timezone or language rarely identify anyone. The problem is the combination: the more characteristics come together, the more unique the browser becomes, and that is how fingerprinting tracks without cookies. That is why this tool is deliberately restrained, it shows the diagnostic to you and sends nothing, avoiding canvas, audio and combinatorial collection. In private windows or with tracking protection, some values (storage, cookies, APIs) may appear restricted.
When requesting technical support, share only what is needed: usually browser, version and system are enough to reproduce a bug. Avoid dumping your whole environment into a public ticket, each extra detail is one more piece of your fingerprint that did not need to be exposed.
Paste the code into your HTML and the tool shows up on your page, without J-Kit's navigation and ads. It still runs in the browser of whoever visits your site.
<iframe
src="https://jkit.tools/embed/en-US/browser-information"
width="100%"
height="600"
style="border:0"
loading="lazy"
title="Browser Information"
></iframe>These references help contextualize formulas, standards, APIs and limitations used on this page. They do not replace professional validation when a result has legal, financial, medical or operational impact.
User-Agent is a string sent by the browser in HTTP requests and exposed via JavaScript. It usually includes browser, engine, operating system and historical compatibility tokens.
Reading happens locally and does not send User-Agent, timezone or capabilities to analytics.