GraphQL vs REST: A Comprehensive Comparison

For decades, REST (Representational State Transfer) was the standard for APIs. Then Facebook released GraphQL, shifting the paradigm from resource-based to query-based fetching.

The Problem with REST

Imagine you want to show a user profile with their 3 recent posts.

REST Approach:

1. GET /users/123 -> Returns ALL user data (name, email, address, etc.). (Over-fetching)
2. GET /users/123/posts -> Returns ALL posts.
3. Client filters the top 3.

You wasted bandwidth downloading unused fields.

The GraphQL Solution

With GraphQL, the client asks for exactly what it needs.

query {
  user(id: "123") {
    name
    email
    posts(limit: 3) {
      title
      excerpt
    }
  }
}

Single Request. Exact Data.

Key Differences

| Feature | REST | GraphQL | | :--- | :--- | :--- | | Endpoint | Multiple (/users, /posts) | Single (/graphql) | | Data Fetching | Fixed structure | Client-defined | | Versioning | v1, v2 (URL based) | Deprecation of fields | | Caching | Easy (HTTP Caching) | Harder (Needs Apollo/Relay) | | Type Safety | Loose (JSON) | Strong (Schema Definition) |

When to use what?

Use GraphQL if:

• You have complex, nested data requirements (e.g., social networks, dashboards).
• You have multiple clients (Mobile, Web, Watch) needing different data shapes.
• You want strong typing between frontend and backend.

Use REST if:

• You want simple, cacheable resources.
• You are building a public API for 3rd party developers (REST is universally understood).
• Your data model is flat and simple.

It's not a war. It's about choosing the right tool for the job.