User-Agent Parser
User-Agent strings are messy historical artifacts, but developers still meet them in logs, analytics tools, bug reports, feature gates, and compatibility checks. A single string may contain browser names, operating system hints, device markers, and rendering engine tokens. The CodeToolia User-Agent Parser provides a lightweight local parser that extracts the likely browser, operating system, device class, layout engine, and mobile or desktop classification. It is not intended to replace a full production-grade UA detection library, but it is helpful for quick inspection when a bug report includes a raw header or a log line contains an unfamiliar client string.
Browser
Chrome
OS
macOS
Device
Desktop
Engine
Blink (AppleWebKit token present)
Mobile/Desktop
Desktop
Rendering engine
Blink (AppleWebKit token present)
About User-Agent Parser
Parse browser, OS, device type, and rendering engine from a User-Agent string. This utility is part of CodeToolia, a collection of tools designed to simplify web development workflows. Like all our utilities, this tool operates entirely on the client side, meaning your data is processed locally within your browser and is never transmitted to any server.
Privacy & Security
We prioritize your privacy. By using browser-based technologies (Web APIs), we ensure that sensitive data—such as API keys, JSON payloads, or personal identifiers—stay strictly within your local environment.
How to use
- Paste a complete User-Agent string into the input area.
- Click Parse User-Agent to extract browser, OS, device, and engine details.
- Treat the result as a practical clue, not a security boundary.
How this tool works
The parser reads common browser, operating system, device, and engine hints from a User-Agent string. It is designed for quick interpretation of logs and support tickets, not for authoritative device identification.
User-Agent strings include historical compatibility tokens, so a single string may mention several browser names. The tool favors practical signals that help humans understand what likely produced the request.
Common use cases
Paste a raw User-Agent from a bug report to check whether the user was likely on mobile Safari, desktop Chrome, Android WebView, or another common client.
Inspect analytics exports and server logs when a layout bug, redirect issue, or feature flag appears to affect only one browser family.
Example
Mozilla/5.0 (iPhone; CPU iPhone OS 17_2 like Mac OS X) AppleWebKit/605.1.15 Mobile/15E148 Safari/604.1
Accuracy and privacy notes
User-Agent values can be spoofed, frozen, reduced, or unusual. Do not use the result as a security boundary.
For production feature detection, prefer capability checks in the browser instead of browser-name rules whenever possible.
User-Agent Parser technical guide
Learn the concept behind this tool, when developers use it, and how to reproduce the same operation in code.
What is User-Agent Parser?
A User-Agent string is a legacy HTTP header that gives hints about the client, browser engine, device, and operating system. In practice, developers need a small focused utility for user-agent parser because raw technical values often arrive without the surrounding explanation that makes them easy to trust. A production log, copied response body, browser console value, support ticket, or staging database row may contain a value that is technically valid but hard to inspect quickly. This page keeps the transformation visible so you can compare input and output before moving the result into code, documentation, or a debugging note.
The important thing to understand is the shape of the data being handled. For User-Agent Parser, the working units are browser tokens, OS tokens, device hints, and rendering engine markers. Those units may look simple, but they often cross system boundaries: browser to backend, backend to database, database to analytics, command-line script to CI pipeline, or documentation to a teammate's local environment. A good developer tool should make those boundaries explicit instead of hiding them behind a black box.
Common use cases
Use this tool when you are reading support tickets, investigating browser-specific bugs, and interpreting analytics or server logs. These are not just convenience tasks. They are the small checks that prevent a developer from shipping the wrong sample, misunderstanding a production issue, or losing time to a value that looked harmless at first glance.
It is also useful during code review and incident response. When a pull request includes a transformed value, a reviewer can reproduce the transformation and confirm that the output matches the intended behavior. During debugging, a fast local check helps narrow the search area before you open a heavier IDE, write a temporary script, or ask another service to process the same data.
Code examples
The snippets below show how to perform the same kind of operation in code. They are intentionally small, because the goal is to connect the browser tool with the runtime you may use in production. Always adapt error handling, input validation, and encoding rules to your own application.
JavaScript
javascriptconsole.log(navigator.userAgent);Python
pythonua = request.headers.get('User-Agent', '')
print(ua)FAQ and implementation notes
What is the most common mistake with this tool? User-Agent strings can be spoofed, reduced, or historically misleading, so they should not be trusted for security decisions. This is why the page includes plain-language notes and examples rather than only a conversion box. The surrounding explanation helps users decide whether the output is appropriate for a quick check, a test fixture, or a production change.
Should I trust the output directly in production? Treat the result as a practical development aid, then verify important behavior in the same runtime, framework, database, browser, or service that will consume the value. Different platforms can disagree on edge cases such as character encoding, timezone display, redirect behavior, regex syntax, cryptographic support, or parser strictness.
Why add documentation below a simple tool? Developer utilities are most valuable when they teach the context around the operation. A conversion result answers one immediate question, but the explanation, use cases, and code snippets help users understand why the result looks the way it does and how to reproduce it in their own systems.
FAQ
Are User-Agent strings reliable?+
They are useful hints, but they can be spoofed or unusual.
Can I use this for security decisions?+
No. User-Agent parsing should not be used as a trusted security control.
Does it support mobile detection?+
Yes. The parser marks common mobile and tablet clients.