What is the curl command

By Thomas Taylor | | 2 minutes
Linux

Curl is a command line utility that was created in 1998 for transferring data using URLs. Fundamentally, curl allows users to create network requests to a server by specifying a location in the form of a URL and adding optional data.

curl (short for “Client URL”) is powered by libcurl – a portable client-side URL transfer library written in C.

Why use the curl command?

Common use cases for curl include:

  • It can download and upload files
  • It has great error logging
  • It allows for quick endpoint testing
  • It provides granular details which aides debugging
  • It is portable and works with most operating systems
  • It is an actively managed open-source tool that is battled tested with a large user base

Base curl command usage

The basic syntax for a curl command is:

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curl [OPTIONS] [URL]

Perform a GET request

The simplest usage is a default GET request for a website or API:

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curl https://pokeapi.co/api/v2/machine/1

Output:

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{"id":1,"item":{"name":"tm00","url":"https://pokeapi.co/api/v2/item/1288/"},"move":{"name":"mega-punch","url":"https://pokeapi.co/api/v2/move/5/"},"version_group":{"name":"sword-shield","url":"https://pokeapi.co/api/v2/version-group/20/"}}

Download a file

Downloading a file using the same name as the remote server:

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curl -O https://github.com/curl/curl/releases/download/curl-8_0_1/curl-8.0.1.tar.gz

Downloading a file and specifying a new name:

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curl -o curl.tar.gz https://github.com/curl/curl/releases/download/curl-8_0_1/curl-8.0.1.tar.gz

Conclusion

curl is a powerful and versatile command line utility that offers a wide range of supporting features: multiple protocols, multiple options, data types, etc.