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Aspen

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Coding & Development

Introduction

Free API testing app for macOS with AI integration.

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Aspen Product Information

Aspen - The Ultimate Free API Testing Tool for macOS with AI Integration

Aspen is a free, native macOS app designed for testing REST APIs locally with zero-trust security. No login is required to run API tests. It integrates AI-assisted capabilities to generate data models, OpenAPI specs, and integration code, helping developers streamline API design, testing, and collaboration. It emphasizes local execution and quick, AI-powered assistance to speed up integrations and development.

What is Aspen?

  • A free, native macOS app for API testing designed around REST APIs.
  • ZERO trust: all operations run locally on your machine; no data is stored or handled externally.
  • AI-assisted: leverage an integrated AI companion to generate data models, OpenAPI specifications, and integration code.
  • Collaboration-ready: introduces Aspen Collections to organize, import/export, and share API requests.
  • No login required: start testing immediately without creating an account.

How it works

  1. Enter the parameters you want to test.
  2. Run tests and receive results in under a second.
  3. Use the AI Companion (Alfred) to speed up integrations, generate code, and create specs.
  4. Utilize Collections to organize and share workflows with teammates.

New features include:

  • Collections for organizing, importing/exporting, and sharing API requests.
  • Import from Postman or export your own requests with a few clicks.
  • Local-first operation ensures data never leaves your machine.

Why use Aspen over alternative tools

  • Zero Trust and Local-Only: all data stays on your device with no cloud storage.
  • No login required: quick onboarding and easier tool adoption.
  • Integrated AI Assistant: accelerate testing, code generation, and API documentation tasks.
  • REST API focus: optimized for designing and testing REST APIs, reducing setup and complexity.
  • Free forever tier: accessible for experimentation and ongoing development needs.

Core Features

  • Zero Trust: all operations run locally with no data storage on external servers
  • No login required: instant access without account creation
  • AI Assistant (Alfred): generate integration code, OpenAPI specs, and data models within the app
  • Native macOS experience: optimized performance for API testing
  • REST API-focused tooling: streamlined for REST API design, testing, and validation
  • Aspen Collections: organize, import/export, and share API requests to speed up collaboration
  • Import/Export compatibility: work with Postman files and other formats