REST vs GraphQL: Which API Paradigm is Right for Your Project?

Quick Overview

Data Fetching Patterns

The fundamental difference is how data is requested and received:

REST: Each resource has its own endpoint. To display a user profile with their posts and followers, you might need 3 separate HTTP requests: GET /users/1, GET /users/1/posts, GET /users/1/followers. Each returns a fixed payload defined by the server.

GraphQL: A single query to /graphql can request all of this data at once, and the client specifies exactly which fields it needs. No over-fetching, no multiple round trips.

Caching

REST APIs benefit from HTTP caching naturally. Each URL represents a resource that can be cached at the CDN, browser, or proxy level. Cache invalidation is straightforward because URLs map to resources.

GraphQL caching is more complex. Since all queries go to a single endpoint with varying payloads, HTTP caching doesn't work out of the box. You need application-level caching (Apollo Client, Relay) or persisted queries to achieve similar caching benefits.

Verdict: REST wins on caching simplicity. This matters significantly for public APIs and high-traffic applications.

Type Safety & Documentation

GraphQL is inherently typed. The schema defines every type, field, and relationship, enabling excellent tooling, auto-completion, and client-side type generation (GraphQL Code Generator).

REST APIs achieve type safety through OpenAPI (Swagger) specifications. With FastAPI, this is automatic. The quality of REST API typing depends on whether teams maintain their OpenAPI specs.

Feature Comparison Table

Feature	REST	GraphQL
Endpoints	Multiple (per resource)	Single (/graphql)
Data Fetching	Fixed response shapes	Client-specified fields
Over-fetching	Common	Eliminated
Under-fetching	Requires multiple requests	Eliminated
Caching	HTTP caching (easy)	Application-level (complex)
File Upload	Simple (multipart)	Complex (multipart spec)
Learning Curve	Low	Medium-High
Tooling	curl, Postman, any HTTP client	Specialized clients needed
Error Handling	HTTP status codes	Always 200 (errors in body)
Versioning	URL or header versioning	Schema evolution

Verdict: Which Should You Choose?

Frequently Asked Questions

Can I use both REST and GraphQL?

Absolutely, and many companies do. A common pattern is REST for public APIs (better caching, simpler for third-party consumers) and GraphQL for internal APIs (flexible data fetching for your own frontend teams). They can coexist in the same system.

Is GraphQL faster than REST?

Not inherently. GraphQL can be faster by eliminating multiple round trips (one query instead of many requests). However, GraphQL queries can also be slower if they trigger expensive nested resolvers. Performance depends on implementation quality, not the paradigm itself.