What should I use for normalized data API?

If you’re building a normalized-data API (i.e., an API over relational/linked data where entities are separated and referenced by IDs), the best choice depends on what you mean by “use.”

Good default choices

1. REST + JSON

Best if you want:

• broad compatibility
• simple caching
• easy debugging
• standard HTTP semantics

Typical pattern:

• /users/1
• /posts/10
• /posts/10/comments

For normalized data, REST works well when:

• each entity has its own endpoint
• nested relationships are represented by IDs or links
• clients fetch what they need

2. GraphQL

Best if you want:

• clients to request exactly the fields they need
• fewer over/under-fetching issues
• strong fit for normalized client-side caches

GraphQL is especially good when:

• your frontend has many related entities
• you want one endpoint for all data access
• you expect evolving client data needs

3. JSON:API

Best if you want:

• a standardized REST-like format
• built-in support for relationships
• clear conventions for normalized resources

JSON:API is often a great fit for normalized APIs because it explicitly models:

• data
• included
• relationships by ID
• resource objects with type and id

Example:

{
  "data": {
    "type": "posts",
    "id": "1",
    "attributes": {
      "title": "Hello"
    },
    "relationships": {
      "author": {
        "data": { "type": "users", "id": "5" }
      }
    }
  }
}

My recommendation

• Use REST/JSON if you want simplicity and broad support.
• Use GraphQL if the client needs flexible, efficient querying.
• Use JSON:API if you want a strong standard for normalized resource structures.

If you mean client-side normalized state management

If your question is about storing API data in a normalized way on the frontend, common choices are:

• Redux Toolkit Query
• Apollo Client (GraphQL)
• TanStack Query + manual normalization if needed

If you want, I can recommend the best option for your specific stack (e.g. React, Node, Python, mobile, etc.).