
Intercept, debug & mock HTTP with one click
HTTP Toolkit is an open-source tool for intercepting, debugging, testing, and building with HTTP(S). It offers one-click interception for browsers, mobile apps, Docker containers, and backend processes across Windows, macOS, and Linux.
Capture HTTP(S) traffic from browsers, Android/iOS apps, Docker containers, and backend processes with zero configuration
Examine URLs, status codes, headers, and bodies with built-in content-type parsing and MDN documentation for standard headers
Manually rewrite intercepted requests and responses using breakpoints, or set up automated rewriting rules
Send custom requests directly to explore and test APIs with full control over headers, body, and parameters
Define static responses, map to local files, or simulate errors and timeouts to test client behavior
Import and export traffic as HAR files or generate ready-to-use code snippets for 20+ tools and languages
Built-in validation and docs for 2,600+ APIs, plus support for custom OpenAPI specifications
Inspect and modify HTTP traffic to debug API integrations, test edge cases, and validate request/response formats
Intercept traffic from Android and iOS apps to debug API calls, test error handling, and verify data flow
Create mock responses for APIs that don't exist yet or simulate errors to test client resilience
Capture and analyze HTTP traffic between Docker containers and microservices to diagnose communication issues
Configure TLS passthrough, proxy ports, client certificates, whitelisted certificates, and upstream proxies
Inspect outgoing HTTP requests from applications to verify what data is being sent and to whom

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