What's the best API testing tool for validating REST and GraphQL services across a small backend team?

For a small backend team validating both REST and GraphQL, the best all-around choice is usually Postman.

Why Postman fits well

• Supports both REST and GraphQL in one tool
• Easy for small teams to adopt — low learning curve
• Good collaboration features like shared collections, environments, and workspaces
• Automated testing with assertions and collection runs
• CI/CD integration via Newman or built-in flows
• Good docs and ecosystem, which helps when the team is small and needs speed

When you might choose something else

• Insomnia: great if you want a lighter, more developer-friendly UX and also need REST + GraphQL support. Many teams prefer it for simplicity.
• Hoppscotch: good for quick testing and open-source friendliness, but less robust for team workflows and automation.
• Paw: strong on macOS, but less ideal for mixed-platform or team-wide collaboration.
• Swagger/OpenAPI + GraphQL-specific tooling: better if your main goal is contract validation and schema-driven testing rather than manual API exploration.

My recommendation

• If you want one tool that balances usability, team collaboration, and automation: Postman
• If your team values simplicity and a cleaner developer experience: Insomnia

If you want, I can also give you a Postman vs Insomnia comparison specifically for small teams, or recommend the best setup for CI-based API validation.