Resonance

Resonance is a local-first, zero-account API client application designed to provide an excellent user experience for testing and interacting with web services.

Features:
- REST/HTTP (HTTP/1.1 and HTTP/2) with all body modes, detailed timing breakdown and cookie display
- GraphQL with query and variables editors, schema introspection, an interactive query explorer and subscriptions over WebSocket
- gRPC with server reflection, local .proto files, all four RPC kinds and TLS/mTLS
- WebSocket, Server-Sent Events and MQTT connections with live status
- Import from OpenAPI 3.x, Swagger 2.0, Postman, Insomnia, HAR captures and cURL commands; export to OpenAPI and Postman
- Code generation in 9 languages and Markdown/HTML documentation generation
- Built-in mock server with response templating, custom bodies, status codes and delays
- Pre-request and test scripts in sandboxed JavaScript with a Postman-compatible pm API
- Collection runner with data files, request tags, run history and JSON/JUnit XML reports
- Response schema validation (JSON Schema drafts 4 to 2020-12) and JSONPath/XPath inspection
- Environments with variable templating and dynamic variables
- Bearer, Basic, API key, OAuth 2.0 with automatic refresh, Digest, NTLM and AWS Signature v4 authentication
- Client certificates (mTLS), keychain-backed secrets and HTTP/HTTPS/SOCKS proxy support
- Git-friendly collections stored as plain files, with the current branch shown in the sidebar
- Workspace tabs, request history with search and replay, and keyboard shortcuts for everything
- Light, dark and system themes with 9 accent colours
- Available in English, German, Spanish, French, Italian and Portuguese (BR)