User Agent Parser
See which browser, OS, device or bot sent a request: one user agent or a whole log.
Paste a User-Agent header from a log, a bug report or your server — or check your own browser.
Result as JSON
Your browser and screen
Read from this browser on this device — nothing is sent anywhere.
Apache and nginx access-log lines work too (combined format, also with extra fields such as X-Forwarded-For), and so do .gz logs.
Results
About the User Agent Parser
Paste a User-Agent string — from a server log, a bug report or an analytics export — to see the browser and its version, the rendering engine, the operating system, the device type, vendor and model, and the CPU architecture. Bots are recognised by matching 1,501 known crawler patterns (search engines, AI crawlers, SEO tools, monitoring services, link-preview bots, HTTP libraries and headless browsers), and the page explains what a user agent cannot tell you, such as Windows 10 versus 11 in a reduced Chrome user agent.
When the page opens it shows your own browser: its user agent, the User-Agent Client Hints that Chromium browsers expose (real platform version, model, architecture, full version list), and the viewport, screen resolution and device pixel ratio. Switch to Many to parse a list or a whole Apache or nginx access log (gzip-compressed .gz logs too): identical user agents are counted, the table sorts by any column and everything downloads as CSV. Parsing uses ua-parser-js 1.x (MIT) and runs entirely in your browser.
How to use it
- Paste a user agent into the box — your own browser’s is filled in when the page opens — or press one of the samples.
- Read the summary and the cards for browser, engine, operating system, device, CPU and bot, plus the notes on what the string hides.
- Check Your browser and screen for Client Hints, viewport, screen size and device pixel ratio, and copy them as JSON for a bug report.
- For many at once, choose Many (bulk), paste one user agent per line or access-log lines (or open a log file, also .gz) and press Parse user agents.
- Sort the table by any column, and download the full result as CSV.
Examples
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/141.0.0.0 Safari/537.36
Chrome 141 on Windows 10 · Desktop · Blink · amd64
“Windows NT 10.0” is also what Windows 11 sends, and “141.0.0.0” is a reduced version — the page says so, and Client Hints reveal the real values.
Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)
Googlebot/2.1 — Search engine crawler
66.249.66.1 - - [03/Oct/2026:10:15:35 +0530] "GET /robots.txt HTTP/1.1" 200 120 "-" "Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html)"
Googlebot/2.1 — taken from the user-agent field, counted with every other request from it.
In the combined log format the user agent is the third quoted field, after the request and the referrer. Extra fields after it — such as the X-Forwarded-For field in nginx’s default “main” format — are skipped.
Common uses
- Finding out which browser and device a bug report or support ticket came from.
- Seeing how much of a site’s traffic is bots, search engines or AI crawlers, from its own access logs.
- Checking what a crawler, an HTTP library or a monitoring service sends before writing robots.txt or firewall rules.
- Collecting browser, screen and Client Hints details for responsive-design and compatibility testing.
What a user agent can and cannot tell you
Browsers deliberately send less than they used to. Chromium-based browsers (Chrome, Edge, Opera, Samsung Internet…) send a reduced user agent: the minor version is always 0.0.0, Windows 10 and 11 both say “Windows NT 10.0”, macOS always says 10_15_7, and Chrome on Android says “Android 10; K” instead of the real version and model. Firefox and Safari also freeze the macOS version. iPadOS Safari asks for desktop sites by default and then sends a Mac user agent.
The details are still available as User-Agent Client Hints in Chromium browsers: Sec-CH-UA, Sec-CH-UA-Mobile and Sec-CH-UA-Platform are sent with every request to an HTTPS site, and a server can ask for more — such as Sec-CH-UA-Platform-Version (13 or higher means Windows 11), Sec-CH-UA-Model or Sec-CH-UA-Full-Version-List — with an Accept-CH response header. Scripts can read the same values with navigator.userAgentData.
Bots and crawlers
Bot detection matches the user agent against the crawler-user-agents list (1,501 patterns, MIT licence) and names the kind of bot: search-engine crawler, AI crawler, SEO tool, uptime monitor, security scanner, link-preview bot, feed reader, HTTP library (curl, python-requests…) or headless browser.
A user agent is only a claim. Any client can send “Googlebot”, and bots that copy a normal browser’s user agent cannot be spotted from it at all. To confirm a crawler, check its IP address the way the search engines document — for Googlebot, a reverse DNS lookup that ends in googlebot.com or google.com, then a forward lookup back to the same IP.
Limitations
- The result is what the client claims: user agents can be changed in a browser’s developer tools or set to anything by scripts.
- Crawler detection only knows listed patterns; new bots, and bots that pretend to be ordinary browsers, are not detected.
- Device models come from the string itself, so many phones show a model code (SM-S918B) and Chrome on Android shows only “K”.
- ua-parser-js stays on version 1.x because version 2 changed to the AGPL-3.0 licence. Very new browsers or devices may be named less precisely until the parser data catches up.
- Bulk mode reads log files up to 100 MB, and gzip-compressed .gz logs up to 100 MB unpacked; the table shows the first 500 rows in the chosen order, and the CSV contains all of them.
Privacy
Everything happens in your browser. What you enter or open here is not uploaded or stored by MySmartCoPilot.
Frequently asked questions
What is my user agent?
It is filled into the box as soon as the page opens, parsed into browser, engine, operating system and device, and shown in full under Your browser and screen together with your Client Hints, viewport and screen size.
Why does my Windows 11 computer show up as Windows 10?
Every browser sends “Windows NT 10.0” on both Windows 10 and Windows 11, so the user agent cannot tell them apart. In Chrome, Edge and other Chromium browsers the Sec-CH-UA-Platform-Version client hint can: a major version of 13 or higher means Windows 11. This page reads it for your own browser.
How can I tell bots from people in my logs?
Switch to bulk mode and paste the log or open the file: every user agent is checked against 1,501 known crawler patterns and the summary shows the share of bot requests and which kinds of bots they are. Remember that bad bots can disguise themselves as browsers.
What are User-Agent Client Hints?
A newer way for Chromium-based browsers to describe themselves: short Sec-CH-UA-… request headers instead of one long string. The basic ones (brand, mobile, platform) are always sent; detailed ones such as the platform version or the device model only when a site asks for them with Accept-CH. Safari and Firefox do not support them.
Why does Chrome on iPhone use the WebKit engine?
Apple requires browsers on iOS and iPadOS to use its WebKit engine, except in a few regions where other engines are allowed (the EU since iOS 17.4, for example), so Chrome (CriOS), Firefox (FxiOS) and Edge on iPhone normally render like Safari. The user agent does not say which engine is in use.
Is the user agent or my log uploaded?
No. Parsing, bot detection and the CSV export all run in your browser; the page downloads its parser once and then works offline.