HTTP & API Toolkit — Free & Private

Status codes, security header analysis, webhook testing, mock responses, GraphQL and OpenAPI helpers, user agents and subnets.

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Tools in HTTP & API Toolkit

HTTP Status Code Reference: Search and browse common HTTP response status codes and what they mean.
HTTP Security Header Analyzer: Analyze HTTP response headers, audit security policies (CSP, HSTS, X-Frame-Options), and calculate security score.
User-Agent Parser: Identify browser, engine, OS, and device type from a User-Agent string.
Webhook Tester: Compose and send test HTTP payloads to a webhook URL
HTTP Mock Response Generator: Create and preview mock HTTP response stubs, headers, and status codes for API testing
Fake API Response Generator: Generate realistic mock JSON datasets with customized field types, arrays, and relational structures
GraphQL Query Builder: Construct and format GraphQL queries, mutations, and variables with visual field tree
OpenAPI & Swagger Validator: Validate OpenAPI 3.x and Swagger 2.0 schemas for structure, missing paths, and syntax errors
Subnet & CIDR Calculator: Calculate IP subnet masks, wildcard masks, network and broadcast addresses, and usable host ranges.