Free Online User Agent String Parser & Decoder

Overview

A high-performance, single-file browser utility designed to parse and decode user agent strings. This tool provides developers, QA testers, and privacy-conscious users with a clear, structured breakdown of the technical information embedded within any user agent string.

Key Features

• Manual Parsing: Paste any custom user agent string to receive an instant, detailed breakdown.
• Auto-Detection: One-click functionality to capture your current browser's user agent string.
• Structured Output: Results are categorized into:
  • Browser: Name, version, and family.
  • OS: Operating system name and version.
  • Engine: Layout engine (Blink, WebKit, Gecko, Trident).
  • Device: Type identification (Desktop, Mobile, Tablet).
• Data Export: Instant JSON view of the parsed results for use in technical documentation.
• Privacy First: Absolutely zero tracking, no cookies, no storage, and no server-side communication.

UI Layout

• Header: Clean, minimalist title centered at the top.
• Main Tool Area:
  • Large text area input for user agent strings with placeholder text.
  • Action buttons: "Parse String" (Primary), "Detect My UA" (Secondary), and "Clear" (Tertiary).
• Results Section: A card-based display grid that populates after analysis. Each section (Browser, OS, Engine) uses clear typography and subtle icons.

Design System & Aesthetics

• Color Palette: Professional light-mode aesthetic.
  • Background: #f8fafc (Slate-50)
  • Cards: #ffffff (White)
  • Text: #1e293b (Slate-800)
  • Accents: #3b82f6 (Blue-500)
  • Borders: #e2e8f0 (Slate-200)
• Animations:
  • Smooth fade-in transitions for result cards.
  • Hover states on buttons with slight scale transformations.
  • Micro-loading indicators while processing.

Development Directives (Strict)

• Single File: All HTML, Tailwind CSS (via CDN), and JavaScript must reside in a single index.html file.
• Storage Restrictions: NO usage of localStorage, sessionStorage, IndexedDB, or cookies. Maintain state exclusively in volatile JavaScript variables.
• Compatibility: Ensure the application functions perfectly within a sandboxed iframe. Do not use blocking calls like alert() or prompt(); build custom CSS/JS modals instead.
• Responsiveness: Use CSS Flexbox/Grid to ensure the tool is usable on all screen sizes (mobile to 4K monitor).
• SEO: Ensure semantic HTML tags (<main>, <section>, <h1>, <h2>) are used correctly to help with search engine indexation.