# Postman Tools > Free, in-browser developer tools from Postman — convert, generate, calculate and check without signing in. Part of the Postman API platform. ## Tools - [JSON to types](https://www.postman.com/tools/json-to-types): JSON to types turns a sample JSON payload into typed model definitions by inferring the shape of the data — no schema, no annotations, and no API documentation required. - [cURL to code](https://www.postman.com/tools/curl-to-code): cURL to code converts a cURL command into the equivalent HTTP request written in your language, so a command copied out of documentation or browser devtools becomes code you can paste into a project. - [RPS calculator](https://www.postman.com/tools/rps-calculator): The RPS calculator estimates the throughput in requests per second that a given number of concurrent virtual users will actually generate, so you can size a load test before running one instead of discovering the number afterwards. - [Website Speed Test](https://www.postman.com/tools/website-speed-test): The website speed checker measures how long a site takes to respond to a real request from a Postman server, reports the total response time and an estimated time to first byte, and grades the result as Fast or Slow. - [Website Uptime Check](https://www.postman.com/tools/website-uptime-check): Is it up? tells you whether a website or API is responding right now by sending a real request from a Postman server and reporting whether anything came back, and how long it took. - [API Health Check](https://www.postman.com/tools/api-health-check): API health check sends a real GET request to any endpoint and shows the status code, response time and payload size, graded Healthy or Unhealthy. - [Test data generator](https://www.postman.com/tools/test-data-generator): The test data generator produces realistic, reproducible sample rows — names, emails, addresses, prices, order statuses and more — and exports them as JSON, CSV, tab-delimited or Excel. - [REST API Client](https://www.postman.com/tools/rest-api-client): REST API Client is a signed-out HTTP client for building and sending requests. - [GraphQL Client](https://www.postman.com/tools/graphql-client): GraphQL Client is a signed-out GraphQL client with schema introspection and a visual query builder. - [gRPC Client](https://www.postman.com/tools/grpc-client): gRPC Client is a signed-out gRPC client for loading protobuf methods, composing messages, and invoking gRPC services through Postman's Cloud Agent. - [MCP Client](https://www.postman.com/tools/mcp-client): MCP Client is a signed-out MCP workbench for connecting to remote HTTP MCP servers and inspecting their capabilities. - [WebSocket Client](https://www.postman.com/tools/websocket-client): WebSocket Client is a client for connecting to WebSocket servers and inspecting bidirectional messages. - [Socket.IO Client](https://www.postman.com/tools/socketio-client): Socket.IO Client is a client for connecting to Socket.IO servers and inspecting bidirectional event messages. - [OpenAPI Editor and Visualizer](https://www.postman.com/tools/openapi-editor-and-visualizer): The OpenAPI visualizer and linter is a browser-based editor that renders an OpenAPI definition as live API documentation while you type, and reports validation and style problems as you go. - [OpenAPI validator](https://www.postman.com/tools/openapi-validator): The OpenAPI validator checks an OpenAPI definition for syntax and schema errors, then scores its design out of 100 against a style guide of API best practices, listing every violation grouped by rule and auto-fixing the mechanical ones in place. - [API Designer](https://www.postman.com/tools/api-designer): API Designer turns a plain-English description of an API into a working OpenAPI 3.1 specification, with paths, operations, schemas and examples already filled in. - [Understand your API](https://www.postman.com/tools/understand-your-api): Understand your API reads an OpenAPI specification and explains in plain English what the API does, how authentication works, and what a consumer needs to know before integrating. - [AI unit test generator](https://www.postman.com/tools/unit-test-generator): The AI unit test generator turns a pasted function into a runnable unit test suite in the framework you choose, covering the normal path and the edge cases the code implies. - [Webhook payload explainer](https://www.postman.com/tools/webhook-payload-explainer): The webhook payload explainer reads a webhook payload or any JSON response and explains what every field means, which ones matter, and what will trip you up when you consume it. - [Mock from OpenAPI spec](https://www.postman.com/tools/mock-from-spec): Mock from OpenAPI spec turns an OpenAPI or Swagger document into a live mock server for every endpoint at once — paste the spec and get a hosted URL that answers each path with an example response, no account and no backend. - [Editable mock API](https://www.postman.com/tools/editable-mock): Editable mock API lets you build a mock endpoint by hand — choose a method and path, write the JSON response, and generate a live URL you can edit in place, with no account and no backend. - [Instant mock API](https://www.postman.com/tools/instant-mock-api): Instant mock API spins up a live endpoint that serves realistic JSON for a common resource — pick users, products, orders or posts and get a URL you can call right away, with no account and no backend to run. - [SSL Certificate Check](https://www.postman.com/tools/ssl-certificate-check): SSL certificate checker tells you when a domain's TLS certificate expires, who issued it, which hostnames it covers, and whether the chain is trusted, by opening a real TLS connection to the host and reading the certificate it presents. - [HTTP Header Check](https://www.postman.com/tools/http-header-check): Response header checker sends one real GET request to a URL and explains every response header that comes back — what it does, what the value you have actually means, and what to change — grouped into security, CORS, caching and payload. - [API load test](https://www.postman.com/tools/api-load-test): API load test runs a real Postman performance run against a URL you enter — pick the number of virtual users and how long to run, and it reports latency, throughput and error rate from Postman’s cloud, no account needed. - [API Monitor](https://www.postman.com/tools/api-monitor): API Monitor schedules a real Postman monitor for a URL you paste, runs it on a repeating schedule from a Postman server, and shows each run — response time, status, and pass/fail — on a live chart. - [Multi-step API Monitor](https://www.postman.com/tools/api-monitor-multistep): Multi-step API Monitor chains two requests into one real Postman monitor — the first signs in and its token is passed to the second — then runs the pair on a schedule and shows every request and response on a live dashboard. ## About - Every tool runs in your browser. Nothing you paste is uploaded, and none of them need an account. - [Postman Tools](https://www.postman.com/tools) — the interactive index. - [llms.txt](https://www.postman.com/tools/llms.txt) — the same index in llms.txt form.