Overview

REST and GraphQL are both HTTP-based API paradigms that differ fundamentally in how clients request data. REST exposes multiple URLs with server-defined response shapes; GraphQL exposes a single endpoint where the client’s query body dictates exactly which fields and relationships to return. The distinction drives decisions around over-fetching, N+1 latency, HTTP cacheability, and schema contracts.

Comparison Diagram

RESTmultiple endpoints, fixed shapeClientGET /usersGET /postsGET /comments3 requestsEach response = full object:{ id, name, email, avatarUrl,createdAt, role, prefs }only name+email needed → over-fetchRelated data → N+1 round-tripsBreaking change → new URL, e.g. /v2/GET · cacheable · status codesGraphQLone endpoint, client-declared shapeClientPOST /graphql1 requestquery (client-authored)query {user(id: 1) {name email}posts { title }}SDL schema (server)type User {name: String!email: Stringposts: [Post]}Response: exactly what was declared{ user: { name, email }, posts: [{ title }] }Schema evolves via @deprecated, no versioningPOST · typed schema · introspectable

Comparison Table

AspectRESTGraphQL
EndpointsOne URL per resource type — GET /users, POST /orders, etc.Single URL (POST /graphql); resource selection is in the query body
Response shapeFixed by the server; client receives all fields the endpoint definesDeclared by the client per query; only the requested fields are returned
Over/under-fetchingChronic: server returns full objects; client discards unused fields or must make extra requests for missing onesEliminated by design: resolvers return only fields the query specifies
HTTP cachingNative: GET responses cache at CDN and browser level by URL + headersNon-trivial: queries are POST bodies; requires persisted queries or APQ for cache-key stability
Type systemOptional — enforced only if you add OpenAPI/JSON Schema; not validated at runtime by defaultMandatory SDL schema; all queries are parsed and validated against it before execution
VersioningBreaking changes typically require new URL paths (/v1/, /v2/) or custom Accept headersAdditive schema evolution with @deprecated directives; a single endpoint surface stays stable
Error handlingHTTP status codes carry semantic meaning: 200, 404, 422, 500, etc.Always 200 OK; errors surface in an errors[] array alongside any partial data
Introspection / discoverabilityRequires an external spec (OpenAPI/Swagger); not built into the protocolBuilt-in: query __schema or __type to get the full type graph at runtime

Key Differences

  • REST has one endpoint per resource; GraphQL has one endpoint for the entire API, and the query body — not the URL — determines what data comes back.
  • REST responses return all server-defined fields for a resource (over-fetch), and fetching related data requires additional round-trips (N+1 problem). A single GraphQL query can traverse multiple types and return exactly the fields requested.
  • REST uses standard HTTP verbs and status codes, making GET-based CDN and browser caching trivially available. GraphQL queries travel as POST bodies, breaking HTTP cache semantics by default and requiring explicit workarounds.
  • GraphQL’s SDL provides a mandatory, introspectable type contract enforced at parse time. REST type contracts are optional add-ons (OpenAPI); the server can return anything without violating the protocol.
  • REST breaking changes typically force a new URL version (/v2/); GraphQL prefers additive schema evolution with @deprecated, keeping a single endpoint surface over the API’s lifetime.

When to Use Each

REST

  • Public APIs Needing CDN Caching: REST’s GET-based requests cache natively at the CDN and browser level by URL and headers, something GraphQL’s POST-based queries can’t do without extra tooling.
  • Simple Resource-Oriented CRUD: When each resource type is consumed independently and maps cleanly to standard HTTP verbs, REST’s one-endpoint-per-resource model needs no extra query layer.
  • Broad Ecosystem Compatibility: REST’s use of standard HTTP status codes and verbs makes it trivially consumable by browsers, curl, API gateways, and generic HTTP tooling.
  • Stable, Infrequently-Changing Contracts: Versioning through new URL paths (/v2/) is straightforward when a small, well-known set of clients can migrate on a fixed schedule.

GraphQL

  • Multiple Clients With Divergent Data Needs: When iOS, Android, and web clients each need different fields, GraphQL lets each declare exactly what it wants instead of REST endpoints multiplying to match every variant.
  • Joined Data in One Round-Trip: Fetching heterogeneous, related data (e.g. a user plus their posts) in a single query avoids the N+1 round-trips REST requires for related resources.
  • Rapidly Evolving Schemas: Additive changes via @deprecated keep a single endpoint surface stable, avoiding the churn of REST’s URL-versioning scheme.
  • Runtime-Discoverable APIs: Built-in introspection (__schema, __type) lets tooling and client codegen inspect the full type graph without maintaining a separate OpenAPI spec.