REST API vs GraphQL: Which Should You Use?

REST and GraphQL are the two dominant paradigms for building APIs today. Choosing between them is one of the most consequential architectural decisions a team makes. Both can serve data effectively, but they make different trade-offs around flexibility, performance, and complexity. This guide breaks down the differences so you can make the right choice for your project.

How REST Works

REST (Representational State Transfer) organizes APIs around resources, each with its own URL endpoint. You use HTTP methods to operate on resources: GET to read, POST to create, PUT/PATCH to update, DELETE to remove. REST APIs are stateless, cacheable, and leverage the full expressiveness of HTTP.

How GraphQL Works

GraphQL is a query language and runtime developed by Facebook. Instead of multiple endpoints, there’s a single endpoint that accepts queries. Clients specify exactly what fields they need, and the server returns precisely that — no more, no less. Mutations handle writes, and subscriptions handle real-time updates.

Over-fetching and Under-fetching

REST’s biggest pain point is over-fetching (receiving more data than needed) and under-fetching (requiring multiple requests to assemble a complete view). GraphQL solves both: clients ask for exactly what they need, often combining data from multiple sources in a single round trip.

Caching

REST has excellent caching support because each resource has a unique URL — HTTP caching at CDN and browser levels is straightforward. GraphQL requests are typically POST requests to a single URL, making HTTP-level caching harder. Client-side caches like Apollo Client handle this with normalized caches, but it adds complexity.

Type System and Documentation

GraphQL’s strongly-typed schema is a major advantage. The schema serves as living documentation, and tools like GraphiQL and GraphQL Playground allow interactive exploration. REST can achieve similar results with OpenAPI/Swagger, but the schema isn’t enforced at runtime.

When to Choose REST

• Simple CRUD applications with well-defined resources
• Public APIs that need aggressive HTTP caching
• Teams already familiar with REST conventions
• When simplicity and wide tooling support matter most

When to Choose GraphQL

• Complex frontends with varied data requirements across views
• Mobile clients where bandwidth is constrained
• Aggregating data from multiple backend services
• When rapid frontend development needs to outpace backend changes

Testing your API? Use the JSON Formatter on devutilitypro.com to pretty-print and validate API responses from both REST and GraphQL endpoints.