User Agent Strings

A user agent string is a piece of text sent in HTTP requests to identify the software making the request. This can include web browsers, mobile apps, command-line tools, and other clients.

User agent strings are commonly used in analytics and server logs to understand what type of client is accessing a website and which operating system it is running on.

This page provides a curated reference of real-world user agent strings, along with an identified client and operating system when that information can be determined from the string itself.

Browse User Agent Strings

Use the list below to browse known user agent strings, or search to find a specific string, client, or operating system.

Each entry links to a dedicated page showing the full user agent string and the client and operating system we can identify from it.

About Client and Operating System Identification

User agent strings are not standardized and often contain historical or compatibility tokens that do not accurately describe the underlying software.

For this reason, the client and operating system shown here represent a best-effort interpretation of the user agent string itself, rather than a guarantee of the environment making the request.

Open-Source Data and Methodology

The user agent data shown on this page is backed by an open-source project that maintains a normalized, curated dataset of real-world user agent strings.

The project focuses on practical, transparent classification rather than heuristic or speculative detection. User agent strings are normalized to reduce noise from version numbers and casing differences, making the data easier to group, review, and maintain over time.

This dataset is actively used in production analytics and is continuously improved through real-world usage and community contributions.

You can explore the dataset, methodology, and contribute updates via the open-source repository.