Common User Agents

The table below consists of a list of common user agent strings and the tools or libraries they are associated with.

What is a User Agent String?

The HTTP spec asks clients to identify themselves by providing a header called "User-Agent". This header's history is pretty chaotic, but the spec does a good job detailing how the header should actually work.

This document lists some of the more common user agent strings that an API might encounter. If you find any are missing, feel free to add them via pull request or create an issue!

Why is this useful?

By tracking the user agent headers received by your API you can get a sense for what languages and libraries are used by your developers. If one language or library is used by many different API consumers, it might be worth supporting that language with an official API library.

The list

Note I do not plan on listing out every possible version number, so you will need to substitue out the version numbers for wildcards.

Source	Example User Agent String	Description	Can be overriden by a developer?
Guzzle	"Guzzle/4.0 curl/7.21.4 PHP/5.5.7", "Guzzle/4.0 PHP/5.5.7"	HTTP library for PHP. The first one uses curl bindings, and the second uses native PHP HTTP functionality	Yes
Requests	python-requests/2.12.4	HTTP library for Python	Yes
Curl	curl/7.47.0	An old, trusted HTTP request tool written in C.	Yes
Insomnia REST client	insomnia/5.0.20	Insomnia is a cross platform HTTP request tool intended to help with API development	Yes
Postman	TBD	Postman is a popular cross platform HTTP request tool intended to help with API development	TBD
Paw	TBD	A common mac-only HTTP request tool intended to help with API development	TBD

Tools that do not provide default user agent strings

Source	Description	Can be overriden by developer?
PHP Curl	PHP's standard curl bindings do not assign a default user agent	Yes
Node HTTP(S)	Node's standard request library for HTTP and HTTPS requests do not assign a default user agent	Yes

Looking for....

Libraries

• .Net
• Java
• Android
• iOS
• Go

Clients

• Postman
• Paw