Free tool What is my user agent — and what can a website see?
Your browser introduces itself to every site you open. This page shows that introduction — the user-agent string and the newer Client Hints — next to the language, time zone, screen and privacy settings any page script can read, then spells out which of them TapCub's analytics script actually sends and keeps.
- Read from your own browser
- Client Hints included
- Values shown, not uploaded
Your user agent and browser details
Everything below is read by JavaScript on this page, in your browser. Copy the UA to paste it into a bug report, or into the user agent parser to compare it with others.
Your user agent appears here once JavaScript runs.Browser
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Engine
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Operating system
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Device type
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In-app browser
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Bot rule match
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Parsed with the same rules as the user agent parser. "Bot rule match" checks your UA against TapCub's 197 bot rules: automation tools and headless browsers match, a normal browser should not.
User-Agent Client Hints
Chromium browsers (Chrome, Edge, Opera, Samsung Internet) expose these instead of putting details in the UA. The first three are sent to every site; the rest a page has to ask for.
| Brands (Sec-CH-UA) | — |
|---|---|
| Mobile (Sec-CH-UA-Mobile) | — |
| Platform (Sec-CH-UA-Platform) | — |
| Platform version | — |
| Real OS, from the hints | — |
| Architecture | — |
| Bitness | — |
| Device model | — |
| Full version list | — |
| 32-bit app on 64-bit Windows | — |
| Form factors | — |
Safari and Firefox do not support Client Hints, so these rows say "not supported" there. A "Not A Brand" entry in the brand list is deliberate: Chrome adds a fake brand so sites cannot rely on an exact list.
What an analytics script can see vs what TapCub stores
Any script on a page can read the values in the second column. The last two columns describe TapCub's web script and collector as they work today, not what analytics tools in general do.
| Signal | Your browser | Does TapCub's script send it? | What TapCub stores |
|---|---|---|---|
| User agent | — | Not by the script: every request carries it in the User-Agent header. | Browser and OS with a two-part version, plus device type. The full string is not stored for visits. |
| IP address | — | Seen by the server with every request; a page script cannot read it. | Not stored. Used for the location lookup and inside the salted visitor ID (IPv6: first 64 bits only). |
| Languages | — | Only the first one (navigator.language). | Yes, up to 12 characters, such as en-US. |
| Time zone | — | Yes. | No. Only a flag when it is UTC, a common trait of server-run bots. |
| Screen | — | Yes, width × height. | A width range on each event and the exact size on the session, used to spot iPads and phones in desktop mode. |
| Window size | — | Only a "smaller than 200 px" bot flag; the size itself only with autocapture click maps. | Only with autocapture, next to click positions. |
| Pixel ratio | — | No. | No. |
| Client Hints | — | Not requested. Chromium sends the three basic hints on its own. | No. The server only checks that they agree with the UA, to catch faked browsers. |
| Cookies enabled | — | The script writes no cookies and no local storage by default. | Nothing on your device. The optional sign-in identity mode stores a device ID only after consent. |
| Do Not Track | — | When on, the script does not load at all, unless the site has switched this check off. | By default, a hit that still arrives is kept only as anonymous aggregate data. |
| Global Privacy Control | — | When on, the script does not load (same switch as Do Not Track). | Also honoured on the server by default: anonymous aggregate data only. |
| Touch support | — | No. | No. |
| Automation flag | — | Yes, as one bit of a bot-signal mask, with headless UA and missing languages. | Only as part of the bot-detection result. |
TapCub's visitor ID is an HMAC-SHA-256 of a secret site salt, the site, the IP address (IPv6: first 64 bits) and browser, OS and device without version numbers. The salt is kept in the default balanced mode and replaced daily in strict mode. Neither the IP nor the UA can be read back from the ID.
Version v1.0Updated Update history
What the values mean
A browser exposes far more than the UA string. Each group below answers a different question a website might ask.
The user-agent string
Names the browser, engine and OS. Since 2022–2023 Chrome freezes most of it — Windows NT 10.0, Mac OS X 10_15_7, Android 10; K and a version ending in .0.0.0 — so on Chrome the string looks almost the same on millions of devices. That is the point: it makes you harder to fingerprint.
Client Hints
The replacement for those frozen details. The three basic hints (brand, mobile, platform) go to every site; platform version, model and full version only go to sites that ask. "Real OS" uses the platform version: 13 or above on Windows means Windows 11.
Language, time zone, screen
Useful for showing the right language or local time, and the raw material of fingerprinting when combined. Analytics tools use them for reports and for bot detection: a UTC time zone and a headless window are classic signs of a server-run bot.
Privacy signals
Do Not Track is an old, voluntary header. Global Privacy Control is newer and recognised under some laws, such as California's CCPA, as an opt-out of sale and sharing. By default, TapCub's script does not load when either is on.
Seeing "Not supported" for Client Hints is normal on Safari and Firefox. Seeing a bot match on your own browser usually means an automation tool or a headless test browser is running this page.
Three things people use this page for
No input needed; the page reads your browser as soon as it loads.
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1
Send your UA with a bug report
Copy the user agent with the button and paste it into the ticket. Add the Client Hints "Real OS" line when the bug only happens on Windows 11 or a specific Android version.
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2
Check a privacy setting
Turned on Global Privacy Control or Do Not Track? The table shows whether your browser actually sends it, and what TapCub does when it sees it.
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3
Compare with your analytics
If your own visit looks wrong in a report — wrong device, wrong OS — compare it with what your browser really claims here, then paste the UA into the parser.
Where each value comes from
All values come from standard browser APIs. None of them needs a permission prompt, which is exactly why analytics and fingerprinting scripts can read them silently.
- Nothing on this page is sent to TapCub or anyone else
- High-entropy Client Hints require HTTPS and a Chromium-based browser
- Your IP address is not readable from a page script; only servers see it
| Value | API | Supported in |
|---|---|---|
| User agent | navigator.userAgent | All browsers |
| Basic Client Hints | navigator.userAgentData | Chromium browsers |
| Detailed Client Hints | getHighEntropyValues() | Chromium, HTTPS only |
| Languages | navigator.languages | All browsers |
| Time zone | Intl.DateTimeFormat().resolvedOptions() | All modern browsers |
| Screen and window | screen.width, innerWidth, devicePixelRatio | All browsers |
| Privacy signals | navigator.doNotTrack, navigator.globalPrivacyControl | GPC: Firefox, Brave, DuckDuckGo and extensions |
One laptop, two descriptions
The same Windows 11 laptop running Chrome 130, as the UA describes it and as Client Hints describe it.
| Question | From the user agent | From Client Hints |
|---|---|---|
| Browser version | Chrome 130.0.0.0 | Chrome 130.0.6723.92 |
| Operating system | Windows NT 10.0 (looks like Windows 10) | Windows, platform version 15.0.0 = Windows 11 |
| CPU | Win64; x64 | x86, 64-bit |
| Device model | Not in a desktop UA | Empty (not a phone) |
Version numbers are illustrative. On an Android phone the gap is bigger: the UA says "Android 10; K" while the hints carry the real Android version and model.
Misreadings to avoid
The values are easy to read and easy to over-interpret.
Concluding you are on Windows 10
Every Windows 11 browser still sends "Windows NT 10.0". Check the Client Hints row instead.
Thinking a fake UA makes you anonymous
Changing the UA alone stands out more, not less: Client Hints, screen and time zone then contradict it, which bot filters notice.
Equating "cookies off" with "not counted"
Cookieless analytics counts visits without cookies. What stops TapCub's script is Do Not Track or Global Privacy Control, not blocking cookies.
Analytics that collects less by design
TapCub was built to answer traffic and conversion questions with the smallest useful set of signals, and to tell bots from people with those same signals.
Cookieless by default
No cookies and no local storage, so there is nothing on the device for a banner to ask about. Visitors are counted with a salted hash on the server.
Learn moreBots kept out of your numbers
User agent, headers, client signals, network and rate together decide what is a person. Bots get their own report.
Learn moreGPC and DNT respected
By default the script stays off when either signal is set, and the collector still treats such a hit as anonymous if one gets through.
Learn moreUser agent questions
Still have a question?
Chat with the team behind TapCub — we usually reply within a few hours on business days.
What is my user agent?
It is the string shown at the top of this page: your browser's self-description, sent in the User-Agent header with every request. It names the browser, version, engine and operating system.
What can a website see about my browser?
Without asking for any permission: the user agent, basic Client Hints, languages, time zone, screen and window size, pixel ratio, touch support, whether cookies are enabled and your Do Not Track / GPC settings. The server also sees your IP address. Location, camera and notifications need a prompt.
Why does my user agent say Windows 10 on Windows 11?
Browsers never updated the "Windows NT 10.0" token. The real version is in the Client Hints platform version: 13.0.0 or higher means Windows 11. The "Real OS" row above does that check for you.
Why are Client Hints "not supported"?
Safari and Firefox have not implemented User-Agent Client Hints. Chromium-based browsers have; the detailed values also need a secure (HTTPS) page.
Can I change my user agent?
Yes: browser developer tools can override it for testing, and extensions can change it permanently. Sites may then serve the wrong layout, and the mismatch with Client Hints and screen size can make bot filters treat you as automated.
Does TapCub store my user agent?
Not as a string. For visits it keeps browser and OS names with a two-part version and the device type, and uses browser, OS and device without versions inside a salted visitor-ID hash. The IP address is not stored.
Does this page send my data anywhere?
The tool does not: every value above is read and displayed by JavaScript in your browser and is not uploaded or shared. Like every page on tapcub.com, the visit itself is counted by TapCub's own analytics, which follows the storage rules in the table above, so your full UA string and IP address are not stored.
Update history
New features, fixes and data refreshes for this tool, newest first.
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· v1.0
LaunchedFirst release.
Data this tool relies on
- Bot and AI crawler rules (same as the TapCub product) — checked 2026-11-10, reviewed every 3 months (next review by 2027-02-10)
Missing something or found an error? Tell us — requests that come up often go into the next update. All tool updates
Count visitors without collecting more than you need
TapCub's script is about 2 KB, sets no cookies, and keeps bots out of your reports.