Aspen.io
Aspen.io: Free native macOS app for API testing with AI assistant — no login, fully local.
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What is Aspen.io?
Aspen.io is a free, native macOS application for REST API testing built with zero-trust philosophy. Operates entirely locally without login, no external data storage. Results in under one second. Includes AI assistant Alfred for generating data models, OpenAPI specs, and integration code. Collections feature lets teams organize, import, export, and share API requests.
Aspen.io pricing
Pricing model: Freemium
Aspen is completely free with a free forever tier. There are no paid plans. The free plan includes: API testing, AI assistant (Alfred), OpenAPI Spec generation, Data model generation, Integration code generation, and Collections for organization and collaboration. No login is required and all features are available at no cost.
Aspen.io pros
- Completely free with no paid tiers or subscriptions
- No login required to start using the tool
- Zero-trust policy with no data stored externally
- All operations performed locally on your machine
- Native macOS app optimized for super-fast performance
- Results returned in less than a second
- Integrated AI assistant Alfred for streamlined workflows
- AI generates data models automatically
- AI generates OpenAPI specifications automatically
- AI generates integration code automatically
- Specifically optimized for REST API testing
- New Collections feature for organizing API requests
- Import API requests from Postman easily
- Export and share API requests for team collaboration
- Streamlined teamwork through shared collections
- No risk of data being stored or handled externally
- Immediate start without account creation
- Super-optimized native Mac App architecture
- Free forever tier includes all core features
- Developed by Treblle API platform company
Aspen.io cons
- Only available on macOS, no Windows or Linux support
- No mobile app version available
- Specifically designed only for REST APIs, not GraphQL
- No cloud storage for API collections
- Requires Mac computer to use at all
- Limited to local testing only, no cloud testing
- No user accounts or team management features
- AI assistant features may have usage limitations
Frequently asked questions about Aspen.io
Is Aspen Free?
Yes, Aspen is a free API testing tool made to help out developers who work on API design and API integrations. It has a free forever tier with no paid plans required.
Why would I use Aspen and not Postman or Insomnia?
Aspen offers several unique advantages: Zero Trust Policy ensures high data security by not saving any data with all operations performed locally; No Login Required means you can start immediately without creating an account; Integrated AI Assistant helps quickly run tests, generate integration code, create OpenAPI Specifications, and develop Data Models in the same interface; Focus on REST APIs means the tool is specifically optimized for these API types, reducing setup and testing time.
Is Aspen owned by a company?
Yes, Aspen is developed by Treblle, an API platform for the entire API Lifecycle. It has a free forever tier and out of the box you get access to API Observability, API Analytics, API Governance, Autogenerated API Docs and A(p)I Assistant products.
What platforms does Aspen support?
Aspen is exclusively a native macOS app. It is only available for Mac computers and does not support Windows, Linux, iOS, or web browsers.
What type of APIs can I test with Aspen?
Aspen is specifically made for testing REST APIs. It is optimized for these types of APIs and may not support GraphQL, gRPC, or other API types.
Do I need to create an account to use Aspen?
No, Aspen has a zero-trust policy and requires no login. You can start using Aspen immediately without creating an account or logging in.
Where is my data stored when using Aspen?
All operations are performed locally on your machine. Aspen does not save any data externally, ensuring no risk of your data being stored or handled outside your computer.
What is the AI assistant Alfred used for?
Alfred is Aspen's integrated AI companion that speeds up integrations and development by helping you quickly run tests, generate integration code, create OpenAPI Specifications, and develop Data Models all within the same interface.
What is the Collections feature in Aspen?
Collections is a new feature that lets you organize, import, export, and share API requests to streamline teamwork and reuse. You can import files from tools like Postman or export your own collections in just a few clicks.
How fast is Aspen for testing APIs?
Aspen is completely free and super-optimized as a native Mac App. Simply put in the parameters you want to test and get results in less than a second.