Scalar

Scalar provides a minimalist interface for API testing, supporting various development environments like macOS, Windows, and Linux. Its key selling point is its tight integration with the OpenAPI specification, allowing users to import and sync OpenAPI files for smooth documentation, API testing, and SDK generation. Scalar also provides offline functionality by default, ensuring reliable use even when not connected to the internet.

Additionally, Scalar includes advanced features for collaboration, though these are optional and available through paid plans.

Key features

• Offline-first design: Operate the API client entirely without internet access.
• OpenAPI integration: Sync OpenAPI files for smooth API documentation and testing workflows.
• Cross-platform: Available for macOS, Linux, Windows, and the web.
• Custom domains: Host your documentation on a custom domain.
• Collaboration tools: Enable team collaboration through real-time sync, available on paid plans.
• Markdown support: Write documentation using Markdown and manage it alongside your code.
• Request testing: Send API requests, manage cookies, headers, and parameters effortlessly.
• Authentication management: Built-in authentication handling for secure API testing.

Best use cases

• API testing: Rapidly test API endpoints across RESTful APIs, handling cookies, headers, and more.
• OpenAPI-based development: Streamline API documentation and testing workflows using OpenAPI files.
• Offline API client: Ideal for developers who require offline functionality for testing.

Pros & Cons

• ✅ Supports offline workflows
• ✅ Strong OpenAPI integration
• ✅ Available on all major platforms
• ✅ Minimalist interface
• ✅ Git-friendly with Markdown and OpenAPI sync
• ❌ Limited advanced collaboration features on free plan
• ❌ Smaller community compared to other API clients