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web-utilities
User Agent Parser
Parse any UA string — browser, OS, device, bots & more, instantly
100% Free
Privacy Focused
Instant Results
Works Everywhere
User Agent Parser
Parse any user agent string instantly. Detect browser, OS, device, engine, and bots. Live parsing, color-coded breakdown, UA Client Hints, system info.
Browser
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Engine
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Operating System
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Device
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CPU Architecture
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Bot / Crawler
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Not a bot
Raw User Agent String
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UA Client Hints
Modern API
Your Browser & System Info
Token Breakdown
| Token | Meaning |
|---|---|
| Parse a user agent string to see the token breakdown. | |
Try a sample user agent:
About This Tool
What is User Agent Parser?
A User Agent (UA) string is a short piece of text that every browser, app, and crawler sends with every HTTP request to identify itself. It contains the browser name and version, rendering engine, operating system, device model, and sometimes signals whether the requester is a bot or crawler. Parsing this string lets you understand exactly who or what is visiting a website.
This tool parses any UA string in real time as you type — no server, no submit button. It detects the browser family and version, rendering engine (Blink, WebKit, Gecko, Trident), operating system with version names (including macOS Sonoma, Ventura, Monterey and all major Windows releases), device type and model (Google Pixel, Samsung Galaxy, Huawei, Xiaomi, Apple iPhone/iPad and more), CPU architecture, and 30+ bots and crawlers including GPTBot, Claude-Web, Bytespider, Googlebot, Bingbot, Discordbot and many others.
The raw UA string is displayed with color-coded tokens so you can see at a glance which parts are product names, version numbers, engine comments, and compatibility tokens. When analysing your own browser, two additional panels appear — the UA Client Hints panel (using the modern navigator.userAgentData API) and the Browser & System Info panel showing screen resolution, viewport, CPU cores, device memory, timezone, languages, and more. You can also copy the full parsed result as formatted JSON with one click.
Features
Powerful Features
Everything you need in one amazing tool
Live Parse As You Type
Instant real-time parsing as you type — debounced 400ms for smooth performance, no submit needed
Color-Coded UA Breakdown
Raw UA string highlighted with color-coded tokens — product names, versions, comments, and comment parts each visually distinct
Device & Model Detection
Detect device type and model — Google Pixel, Samsung Galaxy, Huawei, Xiaomi, OnePlus, Smart TV, Game Console, and more
OS with Version Names
Identify OS with full version names — macOS Sonoma, Ventura, Monterey and all major Windows, Linux, iOS, Android releases
Advanced Bot Detection
Detect 30+ bots including GPTBot, Claude-Web, Bytespider, Discordbot, Slackbot, Googlebot, Screaming Frog, GTmetrix and more
UA Client Hints Panel
Read navigator.userAgentData high-entropy values — platform version, architecture, bitness, model, brands — when available
Browser & System Info
Show screen resolution, viewport, DPR, CPU cores, device memory, timezone, languages, touch points and more from browser APIs
Copy Parsed JSON
Export the complete parsed result as formatted JSON — browser, engine, OS, device, CPU, bot data — with one click
Simple Process
How It Works
Get started in 4 easy steps
1
Paste or Type UA
Paste any UA string or use your current browser UA — auto-detected and populated on load
2
Instant Live Parse
Parsing fires automatically as you type — browser, engine, OS, device, bot all extracted in real time
3
View Full Breakdown
Color-coded raw string, summary cards, token table, Client Hints and system info panels
4
Export or Compare
Copy the parsed result as JSON or try any of 12 sample UAs to compare browsers and devices
Why Us
Why Choose Our User Agent Parser?
Stand out from the competition
Debounced real-time parsing fires instantly — no need to click Parse
Raw UA string color-coded by token type for instant visual understanding
Reads modern navigator.userAgentData API for accurate platform, architecture, and bitness data
Shows screen size, DPR, CPU cores, memory, timezone and 15 browser API values in one panel
Identifies GPTBot, Claude-Web, Bytespider, Discordbot and 26 more crawlers and bots
All parsing done in your browser — no UA data ever sent to a server
Use Cases
Perfect For
See how others are using this tool
Debug Responsive Design
Test exactly how your site detects different devices — use 12 built-in sample UAs to simulate Chrome, Safari, Edge, Samsung, Pixel, iPad and more
Analyze Server Logs
Paste UA strings from server logs or analytics to understand your visitor browser and device distribution
Identify AI Crawlers
Detect modern AI bots like GPTBot, Claude-Web, and Bytespider that are increasingly common in server logs
Extract Structured Data
Copy the parsed result as clean JSON to use in scripts, documentation, or issue reports
Inspect Client Hints
View the UA Client Hints API output alongside the classic UA string to compare legacy vs modern detection
Troubleshoot Browser Bugs
Identify exact browser build, OS version and device model when reproducing platform-specific bugs
Frequently Asked Questions
Everything you need to know about User Agent Parser
User agent strings contain: browser name and version (Chrome 118, Firefox 119, Safari 17), rendering engine (Blink, Gecko, WebKit), operating system and version (Windows 11, macOS 14 Sonoma, Android 14), device type (mobile, tablet, desktop), device manufacturer and model (iPhone 15 Pro, Samsung Galaxy S23), bot/crawler indication (Googlebot, Bingbot). Format follows conventions but not standards - browsers can lie or obfuscate. Modern UAs are complex (100+ characters) to maintain compatibility. Some new UAs are frozen (Chrome on desktop always claims same version to prevent fingerprinting).
User Agent string freezing and Client Hints: Browsers are standardizing UAs to reduce fingerprinting for privacy. Chrome froze desktop UA (always claims same version), uses User-Agent Client Hints (UA-CH) HTTP headers for detailed info when needed. All major browsers include "Mozilla/5.0" for historical compatibility (sites blocked non-Mozilla browsers decades ago). All modern browsers claim "AppleWebKit" and "Chrome" even if not Chrome (for compatibility with sites that only test Chrome). Result: UAs converge on similar strings. Detection now requires: parsing subtle differences, using JavaScript feature detection (preferred), requesting UA-CH headers server-side (modern approach).
Do not rely solely on user agent - can be spoofed, incomplete, or frozen. Best practices: Use CSS media queries for responsive design (@media (max-width: 768px)), check screen size and touch capability in JavaScript (window.innerWidth, "ontouchstart" in window), use User-Agent Client Hints (Sec-CH-UA-Mobile header server-side), combine UA parsing with feature detection. Mobile indicators in UA: "Mobile", "Android", "iPhone", "iPad". Desktop: "Windows NT", "Macintosh", "X11". Edge cases: tablets (may report as desktop), desktop with touch, mobile requesting desktop site. Modern approach: design mobile-first, use responsive layouts, avoid hard device detection when possible.
Yes, easily. User agents are self-reported by browsers and can be changed by: browser extensions, developer tools (Chrome DevTools device emulation), browser settings (Safari allows UA switching), curl/wget --user-agent flag, programming libraries (axios, fetch headers). Why spoof: access mobile/desktop-only sites, avoid bot detection, scraping, privacy (prevent fingerprinting), testing. Implications: never trust UA for security decisions, do not block users based on UA alone, use UA for analytics/optimization not authorization. Detection: combine UA with other signals (screen resolution, touch events, CSS media queries, canvas fingerprinting), use server-side verification (IP reputation, rate limiting, CAPTCHA). User agents are hints, not proof.
Legitimate bots identify themselves clearly: Googlebot: Mozilla/5.0 (compatible; Googlebot/2.1; +http://www.google.com/bot.html), Bingbot: similar pattern with Bingbot identifier, Facebook: facebookexternalhit, Twitter: Twitterbot. Bot indicators: "bot", "crawler", "spider" in UA string, no browser/version info (just user agent name), includes contact URL or email, often includes "compatible" keyword. Verification: reverse DNS lookup of IP (Google IPs resolve to google.com), verify IP against published crawler IP ranges. Bad bots: mimic real browsers (pretend to be Chrome), rapid requests from single IP, no JavaScript execution. Never block bots by UA alone - verify via IP, rate limiting, behavior analysis.
Both have uses. User-Agent string: available immediately client-side (navigator.userAgent), works in all browsers (legacy support), good for basic detection (mobile vs desktop, major browser). User-Agent Client Hints (UA-CH): more accurate device info, reduces passive fingerprinting (privacy), requires server-side request (HTTP headers), not fully supported in all browsers yet (Safari lacks support as of 2026). Best practice: use CSS media queries and feature detection first (most reliable), fallback to UA parsing for analytics/optimization only, implement UA-CH on server for detailed legitimate needs, avoid UA parsing for critical functionality. Modern web prioritizes feature detection over browser sniffing. Use UA parsing for statistics and optimization, not feature availability assumptions.
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