User-Agent Parser & Builder
Inspect any User-Agent string in one click: get the browser and version, rendering engine, operating system, device type and whether it belongs to a known bot or crawler. Then switch to Build mode to generate a realistic, up-to-date User-Agent for any browser and OS combination — perfect for cross-device QA, spoof testing and reproducing device-specific bugs. Everything runs in your browser; nothing is uploaded.
Paste a UA string to inspect, or use your own browser’s User-Agent.
Pick a browser and OS to generate a realistic current User-Agent for testing.
Parsed details will appear here
Paste a User-Agent string to see the browser, engine, OS and device type.
Parsed result
- Browser
- —
- Version
- —
- Rendering engine
- —
- Operating system
- —
- OS version
- —
- Device type
- —
- Bot / crawler
- —
Generated User-Agent
A sample current UA for QA — real version numbers drift as browsers update.
How to use
- Open the Parse tab and paste a User-Agent string into the box.
- Click "Use my browser's UA" to load your own device's User-Agent instantly.
- Read the browser, engine, OS, device type and bot verdict in the result table.
- Switch to the Build tab, pick a browser and operating system to generate a UA.
- Use "Copy result" or "Copy UA" to paste the value into your test or bug report.
Features
- Detects Chrome, Edge, Firefox, Safari, Samsung Internet and Opera
- Identifies rendering engine (Blink, WebKit, Gecko, Trident) with version
- Recognizes Windows, macOS, Android, iOS, Linux and Chrome OS
- Classifies device as desktop, mobile, tablet or bot / crawler
- Flags known bots — Googlebot, Bingbot, GPTBot, AhrefsBot and more
- Builds current, realistic User-Agent strings for any browser + OS pair
Frequently asked questions
What is a User-Agent string?
A User-Agent is a text line every browser sends with each request, describing itself — its name, version, rendering engine and the operating system and device it runs on. Servers and analytics tools read it to tailor responses, and QA teams use it to reproduce device-specific behavior.
How accurate is the parser?
It uses well-tested regular expressions covering the major browsers, engines, operating systems and common bots. Modern User-Agents are deliberately vague (for example every Chromium browser reports "Safari"), so treat results as a strong best-effort read rather than an absolute source of truth.
Are the generated User-Agents real?
They follow the exact format each browser uses and carry recent version numbers, so they are realistic for testing. Because browsers update every few weeks, treat the version numbers as a current sample — bump them if you need to match a specific release.
Can I detect bots and crawlers with this?
Yes. The parser flags known crawlers such as Googlebot, Bingbot, Applebot, AhrefsBot, SemrushBot and AI bots like GPTBot, plus a generic fallback for anything containing "bot", "spider" or "crawler". The device type is then reported as "bot / crawler".
Is my data sent to a server?
No. All parsing and building happen entirely in your browser with JavaScript. No User-Agent string or result is uploaded, logged or stored anywhere.