GraphQL vs REST API

REST (Representational State Transfer) organises resources into separate endpoints (/users, /products, /orders) and uses standard HTTP methods (GET, POST, PUT, DELETE). Each endpoint returns a fixed data structure defined by the server.

GraphQL uses a single endpoint and a typed query language. The client sends a query specifying exactly the fields it needs, and the server responds with only that data. The schema defines available types and their relationships, acting as a contract between frontend and backend.

The most well-known REST problem is over-fetching (receiving more data than needed) and under-fetching (needing multiple requests to get all the information). A product detail screen may require calls to /product/123, /product/123/reviews and /product/123/related, adding latency.

GraphQL solves both problems: a single query retrieves exactly the required fields from multiple resources. However, this comes at a server-side cost: resolving complex queries with multiple relationships can be more computationally expensive than serving optimised REST endpoints with HTTP caching.

GraphQL offers a superior development experience for frontend teams. The typed schema enables autocompletion, real-time validation and automatic TypeScript type generation. Tools like Apollo Studio, GraphiQL and Relay DevTools make API exploration and debugging straightforward.

REST is simpler to implement and debug initially. Tools like Postman, cURL and Swagger/OpenAPI are universally known. However, keeping documentation in sync with the implementation requires discipline, while in GraphQL the schema is the documentation.

GraphQL shines in applications with complex interfaces that combine data from multiple sources: dashboards, mobile applications with bandwidth constraints, and projects where the frontend team needs to iterate quickly without waiting for backend changes.

REST remains the best option for public APIs, third-party integrations, internal microservices with stable contracts, and projects where HTTP caching is critical for performance. It is also more suitable when the backend team has no experience with GraphQL.

The GraphQL ecosystem has matured enormously. Apollo Server and Client dominate the market, but alternatives like urql, Relay and graphql-yoga offer different approaches. On the server side, Hasura and PostGraphile generate GraphQL APIs automatically from PostgreSQL databases.

REST has an immense ecosystem and decades of maturity. OpenAPI (Swagger) standardises documentation, and frameworks like Express, FastAPI, NestJS and Spring Boot offer native support. For most teams, implementing REST is faster because the prior knowledge already exists.

The decision should not be dogmatic. Evaluate the complexity of your interfaces, your team’s capabilities, caching requirements and the integration ecosystem. Many successful projects combine both: GraphQL as an aggregation layer for the frontend and REST for inter-service communication.

If you are starting a project from scratch with an experienced full-stack team, GraphQL can accelerate development. If you need a stable public API or integrate with legacy systems, REST is the most pragmatic option with the least friction.