Alternatives to Scalar API Client
An open-source, OpenAPI-aware API client for sending and testing HTTP requests, from the Scalar API platform. The listings below can replace it for an important use case. Each note says what changes if you switch.
The original
Scalar API Client
An open-source, OpenAPI-aware API client for sending and testing HTTP requests, from the Scalar API platform.
Replacements
Listings that take over the same core job as Scalar API Client.
Postman
The most widely used API client, for sending HTTP requests, organising them into collections and sharing them with a team.
Postman is the most widely used API client, with collections, scripts and mock servers, but it is closed source and effectively requires a cloud account.
Insomnia
An API client for REST, GraphQL and gRPC that can keep everything local or sync through Git instead of a cloud.
Insomnia is an Apache-2.0 desktop client with its own OpenAPI editor, test suites and a CLI for pipelines, though most features expect an account.
Hoppscotch
A fast API client that runs in a browser tab, with a self-hostable workspace if you want one.
Hoppscotch is an MIT-licensed browser client with GraphQL, WebSocket and MQTT support and self-hosting, not tied to an OpenAPI description or documentation platform.
Yaak
An offline-first API client for REST, GraphQL, gRPC, WebSockets and SSE, with requests stored as files you can commit to git.
Yaak is an MIT-licensed desktop client that imports OpenAPI and Swagger files, stores requests for git, and adds gRPC and WebSockets without a cloud account.
Bruno
An API client that saves collections as plain files in a folder, so Git handles the sharing instead of a cloud account.
Bruno is an MIT-licensed offline desktop client saving collections as files for Git, supporting REST, GraphQL, gRPC and WebSocket with a CI runner.
Apidog
An API platform for designing, debugging, mocking and testing APIs, with desktop and web clients.
Apidog combines API design, debugging, mocking and testing in desktop and web clients, but is closed source rather than open source on GitHub.
Restfox
A lightweight, offline-first open-source HTTP client that runs in the browser and on the desktop.
Restfox is a lightweight open-source client usable offline in the browser, without OpenAPI awareness but also without a commercial documentation platform around it.
ReqBin
An online tool for sending REST and SOAP API requests directly from the browser.
ReqBin is a closed-source online tool needing no login, with code snippets and timing breakdowns, but it sends requests from its own servers.
Similar software
Related functionality, not a direct replacement.
Swagger UI
Renders an OpenAPI description as interactive, testable documentation.
Swagger Editor
A browser-based editor for writing OpenAPI definitions and sending live requests to the API.
Stoplight
A web platform for designing OpenAPI descriptions, generating API documentation and running mock servers.
Restish
A command-line client for REST-style APIs that discovers operations and schemas from OpenAPI documents.
Prism
An open-source mock server and validation proxy built from OpenAPI documents and Postman collections.
