API testing tools help developers test endpoints, debug requests, and document APIs. The best API clients in 2025 support REST and GraphQL, provide team collaboration, and automate testing workflows.
🏆 Top API Testing Tools
1. Postman - Most Popular
Price: Free / $12/user/month
Features: Collaboration, automated testing, mock servers, documentation
2. Insomnia - Best UX
Price: Free / $5/user/month
Features: Clean interface, GraphQL support, plugin system
3. Thunder Client - Best for VS Code
Price: Free / $5/month
Features: Lightweight, VS Code native, no separate app
🎁 Final Recommendation
Choose Postman (free or $12/user/month) for most complete feature set and team collaboration. Choose Insomnia (free or $5/user/month) for cleaner interface and GraphQL focus. Choose Thunder Client (free) for lightweight VS Code integration.