restclient.el is described as 'This is a tool to manually explore and test HTTP REST webservices. Runs queries from a plain-text query sheet, displays results as a pretty-printed XML, JSON and even images' and is a HTTP Client in the Development category. There are more than 25 alternatives to restclient.el for a variety of platforms, including Windows, Mac, Linux, Online / Web-based and Chrome OS. Most alternatives are HTTP and API Clients. The best alternative is Insomnia REST Client, which is both free and Open Source. Other great apps like restclient.el are Postman (Freemium), cURL (Free, Open Source), HTTPie (Free, Open Source) and Hoppscotch (Free, Open Source).
Postman is a tool that facilitates the development and use of APIs. Postman provides all the functionality needed to create or simulate API specifications and use the Postman Collection Runner to create tests.
cURL is a computer software project providing a library and command-line tool for transferring data using various protocols with URL syntax: supporting FTP, FTPS, SCP, SFTP, HTTP, HTTPS, TFTP, TELNET, DICT, LDAP, LDAPS and FILE.
Powerful, modern HTTP / REST client for Sublime Text. Requester has an expansive feature set, modern UX, powerful, elegant syntax and first class support for API testing and test automation. It runs on macOS, Windows and Linux. Some features:
If you like the interface of HTTPie but miss the features of curl, curlie is what you are searching for. Curlie is a frontend to curl that adds the ease of use of httpie, without compromising on features and performance.