User Agent Checker — Proxidize

How it works

How the checker reads your user agent

Everything here is read from your browser's own navigator object, the same object every website's server and scripts can already query.

Read the user agent string

We read navigator.userAgent, the single string every browser sends to identify itself, and parse it into a browser, engine, OS and device type.

Add the structured signals

Chromium browsers expose the same identity again as User-Agent Client Hints, plus a few high-entropy details (platform version, architecture, model) gated behind a separate request. We read both and show them side by side.

List what else the page can see

Language, timezone, screen size, CPU threads and other navigator properties are added below, grouped the same way sites group them when building a profile.

What you get

What this tool reveals

A plain-English identity for your browser, plus every raw value it was built from.

Parsed identity

Browser and version, rendering engine, operating system and device type, decoded from the raw string instead of left for you to read by eye.

Raw user agent string

The exact string your browser is sending right now, ready to copy into a bug report or a scraper's header list.

Client Hints

The structured replacement for the UA string that Chromium browsers also send, including the high-entropy values sites have to ask for separately.

Language & time

Your browser's language list, IANA timezone and UTC offset, exactly as a page reads them.

Screen & display

Resolution, available area, device pixel ratio, colour depth and orientation.

Hardware & network

CPU thread count, device memory, touch points, pointer type and connection type, where the browser exposes them.

Filter & inspect

Search across every signal to jump straight to the one you're checking.

Copy & export

Copy the full report as text or download it as JSON to attach to a support ticket or compare across browsers.

Go deeper

Two ways a browser identifies itself

Modern browsers report their identity twice, in two formats with different histories and different reliability.

The User-Agent string

A single free-text string every browser has sent since the 1990s. Decades of browsers copying each other's tokens to avoid being blocked by outdated sniffing scripts means the string alone is now unreliable: a Chrome UA still contains the word 'Mozilla', an Edge UA contains 'Chrome', and an iOS Chrome UA (CriOS) contains 'Safari'. Parsing it correctly means checking the more specific tokens first.

User-Agent Client Hints

Chromium's structured replacement: a short list of brands and versions available immediately, plus a longer list of higher-entropy values (exact platform version, CPU architecture, device model) that a page has to explicitly request. Firefox and Safari don't implement it, so it shows as unsupported there.

Why it matters

Why check your user agent

Confirm what a proxy, VPN or automation tool is actually presenting to the sites you connect to.

See whether an in-app browser (Instagram, Facebook, TikTok) is being used instead of your default one.

Debug a site that renders differently on one browser or device than another.

Check the exact user agent string to hardcode into a scraper's request headers.

See the gap between the UA string a server-side check reads and the Client Hints a client-side script can read.

FAQ

Common questions

Talk to our team

A user agent is the identity string your browser sends with every request, and exposes to scripts as navigator.userAgent. It typically names the browser, its version, the rendering engine and the operating system, so a site can decide how to respond.

Because sites used to block browsers they didn't recognise, and every new browser responded by adding the older names to stay compatible. That's why Chrome's UA contains "Mozilla" and "Safari", and Edge's contains "Chrome" and "Safari" too. Reliable detection has to check the more specific tokens (Edg/, OPR/) before falling back to the generic ones, which is exactly what this tool does.

Client Hints are Chromium's structured, opt-in replacement for the UA string: navigator.userAgentData. A short list (brand names, whether the device is mobile, the platform) is available immediately; the rest (exact platform version, CPU architecture, device model) only comes back if a page explicitly asks for it with getHighEntropyValues(). Firefox and Safari haven't implemented Client Hints, so this tool shows it as unsupported there.

That's expected, and it isn't this tool misreading anything. Since Chrome's User-Agent Reduction (Chrome 107+), Chromium browsers freeze the macOS version in the raw user agent string at 10.15.7 for every Mac, regardless of the real OS version, to cut down on fingerprinting detail. Your actual version shows up in Client Hints instead — this tool flags the mismatch and shows both.

Yes. Browser extensions, developer tools' device emulation, and many automation frameworks can override navigator.userAgent (and, less commonly, userAgentData) to report whatever they choose. This tool reports exactly what your browser is currently presenting, whether that value is genuine or overridden.

Two common causes: a browser extension or automation tool is overriding the user agent, or you're using an in-app browser (opened from a link inside Instagram, Facebook or a similar app) rather than your default browser, which this tool calls out separately when detected.

No. Every value here is read directly from your own browser's navigator and screen objects and stays on this page. Nothing is sent to or stored on Proxidize servers.

More tools

Related tools

Other free Proxidize tools for checking how you appear online.

Browser Fingerprint

Your user agent is one signal among many. See the fuller set sites can combine into a cookie-free ID.

WebRTC Leak Test

See whether WebRTC exposes your real IP address while you sit behind a proxy or VPN.

Proxy Extension for Chrome

Full proxy manager for Chrome with built-in WebRTC leak protection.

From the blog

Browser Fingerprinting

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