User-Agent Parser
Parse and analyze browser user-agent strings
User agent strings can be reduced or spoofed. Results describe recognizable tokens and may not identify the actual device or rendering engine.
Example user agents
Paste a user agent or choose an example.
Parsed information
Browser
- Name
- —
- Version
- —
Operating system
- Name
- —
- Version
- —
Device
- Type
- —
- Vendor
- —
- Model
- —
Engine token
- Name
- —
- Version
- —
Your current screen & display
These measurements describe your current device, not the device in the pasted user agent.
- Screen resolution
- —
- Available area
- —
- Viewport
- —
- Pixel ratio
- —
- Color depth
- —
About the User Agent Parser
Our free user agent parser breaks down any user agent string into its core components: browser name & version, operating system & version, device type, and rendering engine. Simply paste a UA string or let the tool auto-detect your current browser to get a full breakdown in seconds.
Every HTTP request includes a user agent string that identifies the client to the server. Parsing this string is essential for cross-browser debugging, log analysis, device-specific content serving, and understanding your audience's technology profile. Our parser handles all major browsers, operating systems, and device families with reliable pattern matching.
The tool also displays screen & display information for your current device, including resolution, viewport size, pixel ratio, and color depth. You can export the full report as a text file or JSON for sharing with teammates or attaching to bug reports.
Key Features
- Browser detection: Chrome, Firefox, Safari, Edge, Opera & more
- OS identification: Windows, macOS, Linux, Android & iOS with version details
- Device classification: desktop, mobile & tablet with vendor and model info
- Rendering engine parsing: WebKit, Gecko, Trident & Presto
- Screen & display metadata: resolution, viewport, pixel ratio & color depth
- Auto-detection of your current browser's user agent on page load
- Pre-loaded example UA strings for Chrome, Safari, Firefox & Android
- Export results as plain text or JSON
- Real-time parsing that updates instantly as you type
- Clean, responsive interface with dark mode support
How to Use
- View your current UA: On page load, your browser's user agent string is automatically parsed and displayed.
- Paste a custom UA string: Replace the text in the input area with any user agent string you want to analyze.
- Try an example: Click one of the example buttons (Chrome on Windows, Safari on iPhone, etc.) to load a sample UA.
- Review parsed details: Check the browser, OS, device, and engine panels for structured information.
- Export the report: Click "Download as Text" or "Download as JSON" to save the parsed results for your records.
Use Cases
- Cross-browser debugging: Identify the exact browser version and engine behind a rendering bug reported by a user.
- Server log analysis: Parse UA strings from access logs to understand traffic by browser, OS & device type.
- Device-specific content delivery: Serve mobile-optimized pages, app install banners, or desktop-only features based on device type.
- Analytics & audience research: Break down visitor demographics by browser and OS to prioritize testing efforts.
- QA & testing: Verify that test requests carry the expected UA string and that server-side UA detection logic is correct.
- Security investigation: Identify unusual or spoofed user agents in traffic logs that may indicate bot activity.
- Bug report enrichment: Export a JSON report and attach it to issue tickets so developers know the exact client environment.
Frequently Asked Questions
What is a user agent string?
A user agent string is a text identifier sent with every HTTP request that tells the server which browser, operating system, and device the visitor is using.
Can I parse user agents from server logs?
Yes. Copy any UA string from your server's access log and paste it into the input field to see its parsed breakdown.
Why does my browser show "Unknown" for some fields?
Some browsers use non-standard or minimal UA strings. If a field cannot be reliably detected, it is displayed as "Unknown" rather than guessing incorrectly.
Does this detect bot user agents?
The parser identifies standard browser UAs. Bot strings (like Googlebot) may show partial results since they follow different conventions.
Tips & Best Practices
- Auto-detect first: Let the tool parse your own browser's UA on load to verify it is working correctly before pasting external strings.
- Use JSON export for automation: Download the JSON report and feed it into scripts or CI pipelines for automated environment checks.
- Compare multiple UAs side by side: Open the tool in two tabs to compare parsed results from different user agent strings.
- Check the rendering engine: Two browsers may look different but share the same engine (e.g., Chrome and Edge both use WebKit/Blink).
- Include screen info in bug reports: The screen resolution, viewport, and pixel ratio sections provide valuable context for reproducing display issues.
- Do not rely solely on UA for security: User agent strings can be easily spoofed, so never use them as the sole basis for access control decisions.