Stoplight

Stoplight (stoplight.io) is an API design and documentation platform centred on the design-first philosophy — the idea that APIs should be thoroughly designed and reviewed before a single line of code is written. Built around the OpenAPI specification (formerly Swagger), Stoplight gives technical and non-technical stakeholders a visual interface to create, edit, and collaborate on API designs without needing deep YAML or JSON expertise. It is owned by SmartBear, the same company behind Swagger, and supports both OpenAPI v2 and v3 alongside JSON Schema modeling.

Stoplight's core value is consistency at scale: as an API portfolio grows, keeping designs coherent across teams becomes increasingly difficult. Stoplight addresses this with style guides and linting rules that automatically flag deviations from defined standards, reusable components that can be shared across endpoints and projects, and a hosted documentation platform that auto-generates interactive API references from OpenAPI specs. The free tier supports individual developers with one project, making it a genuine entry point for teams exploring design-first API workflows before committing to a full subscription.

How Stoplight Works

You create a project in Stoplight and connect it to a Git repository (GitHub, GitLab, Bitbucket, or Azure DevOps), or work directly in the Stoplight web editor. APIs are designed using a form-based visual editor — you define endpoints, request parameters, request bodies, and response schemas by filling in fields rather than hand-editing YAML. Stoplight simultaneously shows the raw OpenAPI YAML in a split-screen "write" mode alongside a visual "read" mode for reviewing the rendered API design. Style guide rules run automatically and highlight violations inline. Once design is complete, Stoplight generates hosted interactive documentation and a mock server, allowing frontend teams to start building against the API contract before the backend is implemented.

Key Features

• Visual OpenAPI editor — form-based design interface for creating OpenAPI v2 and v3 specifications without hand-editing YAML or JSON
• Style guides and linting — define and enforce API design standards automatically across the entire API portfolio with inline violation highlighting
• Reusable components — shared models, parameters, and response schemas that propagate changes across all endpoints using them
• Mock servers — automatically generated mock servers from OpenAPI specs, enabling parallel frontend and backend development
• Interactive documentation — hosted API reference documentation with a built-in "Try It" console generated automatically from the OpenAPI spec
• Git integration — sync with GitHub, GitLab, Bitbucket, and Azure DevOps to keep API specs version-controlled alongside source code
• JSON Schema modeling — visual interface for building and managing JSON Schema definitions shared across API endpoints
• Portfolio-wide visibility — overview of all API projects, their design quality scores, and style guide compliance across teams
• SmartBear community support — backed by SmartBear's global API tooling community for documentation, tutorials, and peer support
• Free tier — one user, one project, full visual editor, mock servers, and interactive documentation at no cost

Stoplight Pricing

• Free — $0/month — 1 user, 1 project. Full visual API designer, mock servers, interactive documentation, and Git sync. Ideal for individual developers evaluating the design-first workflow.
• Professional — $100/month — Multiple users and projects, team collaboration features, advanced style guide governance, private documentation hosting, portfolio-wide visibility, and priority support.

Enterprise plans are available for large organisations requiring custom SSO, advanced access controls, and dedicated support. Always verify current rates at stoplight.io/pricing.

Who Should Use Stoplight?

Stoplight is ideal for API-first product teams, developer experience (DevEx) teams, and platform engineering groups who want to standardise API design across multiple teams and enforce consistent contracts before development begins. Its visual editor makes it accessible to product managers and technical writers who need to contribute to API design without writing raw YAML. It is particularly strong when used alongside a backend framework or API gateway — Stoplight handles design, governance, and documentation, while the gateway handles runtime traffic management. Stoplight is not a full API management platform and does not handle request routing, rate limiting, or runtime policy enforcement; teams needing those capabilities should pair it with a gateway like Gravitee or Kong.

Frequently Asked Questions