Generate mock endpoints from OpenAPI specs — example responses shaped for immediate frontend work, no backend wait while real backends are still being built. Code never leaves your device — formatting and validation run locally in your browser.
Content reviewed October 2026 · About Toolzum
Generate realistic mock JSON from field specs — names, emails, dates, nested objects. Fill frontends before backends exist — local generation, free, no signup.
Generate Swagger UI / OpenAPI specs from a simple description. Enter title, version, and endpoints to produce a complete spec JSON.
Generate Markdown API documentation from OpenAPI specs with endpoints and examples. Publish clean reference docs fast — local conversion, free, no signup.
Generate natural-sounding speech from text using your browser's built-in voices. Adjust speed and pitch — download your text as .txt.
Generate a free disposable email address (temp mail / throwaway email) that receives mail for 60 minutes. Inbound only — you cannot send or reply. Perfect for signups you don’t trust, confirmation codes, and keeping your real inbox spam-free.
Mock endpoints returning example responses shaped by your OpenAPI spec.
Frontend work starts immediately instead of waiting on the real API.
Spec examples drive responses; edit them to shape edge cases.
No — generation runs locally in your browser, free with no signup.
API Mock Data Generator
Generate realistic mock JSON from field specs — names, emails, dates, nested objects. Fill frontends before backends exist — local generation, free, no signup.
Mock API Response Generator
Craft canned API responses with status codes, headers, and bodies for testing error paths. Simulate 404s and 500s without a server — local, free, no signup.