curl and HTTP Command-Line Tools Cheat Sheet

Updated 2026-05-20

curl is a command-line tool and library for transferring data across dozens of protocols — HTTP, HTTPS, FTP, SFTP, SMTP, and more — making it the universal Swiss Army knife for network operations. It is pre-installed on macOS and Windows 10+ and powers over 20 billion installations worldwide, from embedded devices to CI pipelines. Understanding the difference between curl's flag-heavy but precise syntax and the friendlier alternatives (HTTPie, wget) determines which tool fits each job: curl for scripting and API work, wget for recursive downloads, HTTPie for interactive API exploration.

What This Cheat Sheet Covers

This topic spans 16 focused tables and 116 indexed concepts. Below is a complete table-by-table outline of this topic, spanning foundational concepts through advanced details.

Table 1: Core HTTP MethodsTable 2: Sending Data and Request BodiesTable 3: Request HeadersTable 4: Authentication MethodsTable 5: TLS and Certificate OptionsTable 6: Verbose Output and DebuggingTable 7: Response Timing and Metrics with --write-outTable 8: File Download OptionsTable 9: Redirect HandlingTable 10: Cookie HandlingTable 11: Proxy ConfigurationTable 12: Connection and Retry OptionsTable 13: HTTP Protocol Version FlagsTable 14: curl Scripting Patterns and TipsTable 15: HTTPie — Human-Friendly HTTP ClientTable 16: wget — Recursive Downloading and File Mirroring

Table 1: Core HTTP Methods

Every REST API interaction maps to an HTTP verb; curl sends them all via -X or implied defaults.

Command	Example	Description
GET request	`curl https://api.example.com/users`	Default method — no `-X` flag needed; retrieves the resource at the URL.
POST request	`curl -X POST -H "Content-Type: application/json"` `-d '{"name":"alice"}' https://api.example.com/users`	Creates a new resource; `-d` implicitly sets method to POST and Content-Type to `application/x-www-form-urlencoded` unless overridden.
PUT request	`curl -X PUT -H "Content-Type: application/json"` `-d '{"name":"alice","age":30}' https://api.example.com/users/1`	Fully replaces the resource; must supply the complete representation.
PATCH request	`curl -X PATCH -H "Content-Type: application/json"` `-d '{"age":31}' https://api.example.com/users/1`	Partially updates a resource — send only the fields that change.

Table 1: Core HTTP Methods

Every REST API interaction maps to an HTTP verb; curl sends them all via -X or implied defaults.

Command	Example	Description
GET request	`curl https://api.example.com/users`	Default method — no `-X` flag needed; retrieves the resource at the URL.
POST request	`curl -X POST -H "Content-Type: application/json"` `-d '{"name":"alice"}' https://api.example.com/users`	Creates a new resource; `-d` implicitly sets method to POST and Content-Type to `application/x-www-form-urlencoded` unless overridden.
PUT request	`curl -X PUT -H "Content-Type: application/json"` `-d '{"name":"alice","age":30}' https://api.example.com/users/1`	Fully replaces the resource; must supply the complete representation.
PATCH request	`curl -X PATCH -H "Content-Type: application/json"` `-d '{"age":31}' https://api.example.com/users/1`	Partially updates a resource — send only the fields that change.