REST vs GraphQL

1. What is REST vs GraphQL

REST and GraphQL are two popular approaches for building APIs. REST (Representational State Transfer) is an architectural style that uses HTTP methods (GET, POST, PUT, DELETE) on resource endpoints. Each endpoint typically returns a fixed data structure. GraphQL is a query language for APIs that allows clients to request exactly the data they need, no more and no less. Instead of multiple endpoints, GraphQL typically has a single endpoint that accepts queries specifying the shape of the desired data. REST is simpler and more cache-friendly, while GraphQL offers more flexibility and can reduce over-fetching and under-fetching of data.

2. Why It Matters

Choosing the right API architecture affects development speed, frontend/backend coordination, performance, and maintainability. REST is great for simple CRUD operations, caching, and when the API structure is stable. GraphQL excels when clients have diverse data needs, when you want to reduce round-trips, or when you need flexibility in data fetching. Understanding the trade-offs helps you design better APIs that match your application requirements.

3. Example

// REST - Multiple requests
GET /users/123 → { id, name, email, ... }
GET /users/123/posts → [{ id, title, ... }, ...]
GET /users/123/comments → [{ id, text, ... }, ...]

// GraphQL - Single request
query {
  user(id: "123") {
    name
    posts { title }
    comments { text }
  }
}

REST requires multiple requests for related data and may return more data than needed. GraphQL fetches exactly what you need in a single request.

4. Common Mistakes