User-Agent Parser

What you can do with this User-Agent tool

• Parse any User-Agent string in your browser
• Detect browser name, version, and major version
• Identify operating system and normalized OS version
• Classify device type: desktop, mobile, tablet, or bot
• Detect rendering engine (Blink, WebKit, Gecko, Trident, EdgeHTML)
• Flag common crawlers and possible automation indicators
• Inspect raw tokens and export structured JSON
• Private by design: nothing is sent to a server for parsing

What Is a User-Agent?

A User-Agent (UA) is an HTTP header value that identifies the software making a request. Historically it helped servers choose compatible HTML, CSS, or redirects. Today it is still widely logged for analytics, bot filtering, and support, even as browsers reduce how much detail they expose.

A typical desktop Chrome string starts with Mozilla/5.0, then lists a platform in parentheses, followed by WebKit/Chrome compatibility tokens. Those tokens are conventions — not a formal schema — which is why parsers use ordered signature matching.

What Information Can a User-Agent Reveal?

• Browser product and version (Chrome, Firefox, Safari, Edge, Opera, and others)
• Operating system family and version hints (Windows, macOS, iOS, Android, Linux, ChromeOS)
• Device class clues (mobile, tablet, desktop) and sometimes vendor or model tokens
• Rendering engine signals such as Blink, WebKit, Gecko, or Trident
• Crawler or automation indicators when the client declares them

How Does User-Agent Detection Work?

This parser uses deterministic token and signature matching. More specific browser marks are checked before generic ones so Edg/ becomes Microsoft Edge and OPR/ becomes Opera instead of Chrome. OS versions such as 10_15_7 are normalized to readable dotted versions. When evidence is missing or ambiguous, fields stay Unknown.

Example User-Agent Strings

Why Can User-Agent Detection Be Inaccurate?

• Browser vendors freeze or reduce User-Agent detail for privacy.
• Compatibility tokens (like Safari/ in Chrome) exist for legacy sites and can confuse naive parsers.
• Clients can spoof any string; UA parsing is declaration, not authentication.
• Windows NT 10.0 appears for both Windows 10 and Windows 11 in many browsers, so this tool labels it Windows 10/11.
• Desktop-class iPadOS may resemble macOS; unsupported guesses are avoided.

Is User-Agent Parsing Safe?

On Toolshelf, yes for privacy of the paste itself: parsing runs entirely in your browser and is not sent to our server for analysis. Treat User-Agent strings as untrusted text (never execute them). For how Toolshelf handles cookies and site analytics, see the Privacy Policy.

Common ways people use this parser

• Debug client reports

  Decode User-Agent strings from bug reports, analytics exports, or support tickets to see browser and OS context quickly.

• Validate bot traffic claims

  Check whether a log line declares Googlebot, Bingbot, or another crawler signature before you dig into IP verification.

• QA across devices

  Paste sample mobile, tablet, and desktop User-Agents while testing responsive behavior or client hints fallbacks.

• API and middleware checks

  Confirm how your edge rules or middleware would classify a given User-Agent without deploying experimental code.

• Learn UA structure

  Use the token breakdown to understand how Mozilla/5.0 strings pack OS, engine, and browser tokens.

• Privacy-conscious inspection

  Analyze sensitive production User-Agents locally when you do not want to paste them into a third-party SaaS parser.

How to parse a User-Agent on Toolshelf

1. 1Paste a User-Agent, choose a sample, or use Parse My User-Agent.
2. 2Click Parse to extract browser, OS, device, engine, and bot fields.
3. 3Review the cards, open raw token details, then copy fields or download JSON.

Frequently asked questions

What is a User-Agent string?

A User-Agent string is a short text header that a client (usually a browser, app, or crawler) sends with HTTP requests to describe itself. It typically includes tokens for the browser product, rendering engine, operating system, and sometimes device clues.

What does a User-Agent parser do?

A User-Agent parser reads that string and extracts structured fields — browser, version, OS, device type, engine, bot status, and platform hints — so you do not have to decode the tokens by hand.

How can I find my browser User-Agent?

On this page, click “Parse My User-Agent” to read navigator.userAgent from your browser. You can also open developer tools, check network request headers, or visit about:version-style pages depending on the browser.

Can a User-Agent reveal my device?

Sometimes. Many mobile User-Agents include Android versions and model codes, and Apple devices often expose iPhone or iPad. Modern browsers increasingly reduce detail, so exact phone models are often unavailable or unreliable.

Can User-Agent strings be spoofed?

Yes. Clients can set almost any User-Agent value. This tool identifies what the string declares; it does not prove the request genuinely came from that browser or crawler. For bots, verify via reverse DNS and official IP ranges when authenticity matters.

Why does my browser show a different User-Agent?

Browsers freeze or reduce User-Agent values for privacy and compatibility. Extensions, developer overrides, and “request desktop site” modes can also change what is sent. The string you paste here is analyzed as-is.

Can User-Agent parsing identify exact phone models?

Only when the model appears in the string (for example Pixel 8 or SM-S918B). Many User-Agents omit the model. When it is missing, this tool reports Unknown rather than guessing.

Does this User-Agent Parser send my data to a server?

No. Toolshelf parses User-Agent strings locally in your browser with JavaScript. Your input is not uploaded for analysis.

What is the difference between User-Agent and Client Hints?

The classic User-Agent is one header with many packed tokens. Client Hints (Sec-CH-UA-*) are separate, structured headers that browsers can send for brand, platform, and mobile status with more privacy control. This tool focuses on parsing the classic User-Agent string.

Do I need an account to use this User-Agent parser?

No. Toolshelf User-Agent Parser & Analyzer requires no account and no uploads required.

Related tools

• JSON Formatter & Minifier — pretty-print and validate JSON payloads from APIs or exports.
• Text Compare — diff two User-Agent strings or log lines side by side.
• Cron Expression Generator — build and explain crontab schedules.
• Unix Timestamp Converter — convert epoch times from the same logs you are inspecting.