REST vs GraphQL vs gRPC: When to Use What

Let’s be honest — if you’ve been building APIs for a while, you’ve probably faced this question at some point:
“Should I just go with REST, try GraphQL, or dive into gRPC?”

The truth is, there’s no one-size-fits-all answer. Each has strengths, weaknesses, and “gotcha” moments that can make or break your project depending on your needs. So, let’s break it down in a way that’s simple, practical, and based on real-world use cases.

REST — The Old Reliable

REST (Representational State Transfer) has been around for decades, and chances are, your first API call was a REST call. Think of it as the “HTTP for humans.”

✅ Pros

• Simple & Universal: Works with plain old HTTP. If you can send a GET or POST, you can use REST.
• Human-readable: JSON responses are easy to parse and debug.
• Tooling support: Almost every framework and tool has REST baked in.

❌ Cons

• Overfetching/Underfetching: Classic problem. You often get too much or too little data.
• Multiple round-trips: Sometimes you need to hit multiple endpoints to get related data.

Real-world use case

If you’re building a public API (like Twitter or GitHub’s), REST is usually the go-to. It’s easy for third-party developers to consume, and documentation is straightforward.

Tip: Keep your REST endpoints clean and predictable. /users/123/posts feels natural; /data?type=user&uid=123&mode=posts does not.

GraphQL — The Data Buffet

GraphQL is like going to a buffet and choosing exactly what you want on your plate. Instead of calling multiple REST endpoints, you just ask for the exact fields you need in a single request.

✅ Pros

• No overfetching/underfetching: You define the response shape.
• Single endpoint: Everything goes through one endpoint (/graphql).
• Strong typing: Queries and schemas enforce structure.

❌ Cons

• Complexity: Requires a GraphQL server and schema management.
• Caching is harder: REST leverages HTTP caching; GraphQL needs custom solutions.
• Overhead for small projects: Sometimes feels like overkill for simple APIs.

Real-world use case

If you’re building a client-heavy app (like a React Native app or a complex dashboard) where you don’t want to make 10 API calls to render a single page, GraphQL shines.

Tip: Don’t blindly expose your entire database via GraphQL. Define what’s actually needed, otherwise you’ll end up with performance bottlenecks when someone writes a query from hell.

gRPC — The Speed Demon

gRPC is Google’s take on high-performance APIs, and it’s all about speed and efficiency. Instead of JSON, it uses Protocol Buffers (protobufs), which are compact and binary.

✅ Pros

• Super fast: Binary protocol is smaller and faster than JSON.
• Strongly typed contracts: Protobufs define clear contracts between client and server.
• Streaming support: Perfect for real-time communication.

❌ Cons

• Not human-friendly: Harder to debug compared to JSON.
• Limited browser support: Works better for backend-to-backend than frontend-to-backend.
• Learning curve: Requires understanding protobufs and tooling.

Real-world use case

If you’re building microservices that talk to each other inside a data center, or you need real-time features (like chat, live updates, or streaming telemetry), gRPC is a beast.

Tip: Use gRPC for service-to-service calls, but expose REST or GraphQL for your frontend. This way, you get speed internally and usability externally.

The Decision Framework — Which One Should You Pick?

Here’s how I usually think about it in real projects:

• REST: If it’s simple, public-facing, or needs broad compatibility.
• GraphQL: If the frontend team is constantly saying “the API doesn’t give us exactly what we need.”
• gRPC: If you need blazing fast, strongly typed, real-time backend-to-backend communication.

Think of it like tools in a toolbox. You wouldn’t use a hammer to screw in a bolt, right? Same with APIs.

Final Thoughts

Don’t fall into the trap of picking something just because it’s trendy. I’ve seen projects use GraphQL where a couple of clean REST endpoints would have done the job. I’ve also seen teams struggle with gRPC just because they thought “Google uses it, so we should too.”

Use REST when you want simplicity, GraphQL when your clients demand flexibility, and gRPC when performance and scalability are non-negotiable.

And remember — the best API is the one that makes your team’s life easier, not harder.