REST API vs GraphQL: Which is Better?

How REST Works

A REST API exposes multiple fixed endpoints, each returning a predetermined shape of data: `GET /users/5` returns a user, `GET /users/5/posts` returns their posts. Each endpoint has a fixed response structure defined by the server.

This is simple to understand, easy to cache (URLs map naturally to CDN caching), and has universal tooling support. Its downside is over-fetching (a mobile app might only need a user's name but the endpoint returns their entire profile) and under-fetching (needing three separate requests to assemble one screen's data).

How GraphQL Works

GraphQL exposes a single endpoint. The client sends a query describing exactly the fields it needs, and the server returns exactly that shape — nothing more, nothing less.

query { user(id: 5) { name posts { title } } }

This solves over-fetching and under-fetching directly: one request gets exactly what the screen needs, regardless of how many underlying data sources it touches.

The Real Trade-offs

REST is simpler to build, secure, and cache at the HTTP level — a huge advantage for public APIs and CDN-friendly content. GraphQL requires more backend setup (a schema, resolvers) and needs its own caching strategy since every request technically hits the same URL.

GraphQL genuinely shines when a single client (like a mobile app) needs data assembled from many different sources, or when different clients (web, iOS, Android) need meaningfully different shapes of the same data without maintaining separate REST endpoints for each.

Which One Should You Learn First?

Learn REST first. It's still the default for the vast majority of APIs you'll encounter professionally, it maps directly onto how HTTP itself works, and understanding it makes GraphQL's design decisions much easier to appreciate afterward. In our backend development training, students build several REST APIs before we introduce GraphQL as an alternative approach.