REST vs gRPC

Compare communication protocols, payload efficiency, and transport optimizations in modern APIs.

Goal: Compare how REST and gRPC change payload size, latency, and call patterns.Try: Run the comparison in all three scenarios, especially streaming, and watch the overhead bar and call count.

Concept Snapshot

REST prioritizes simplicity and compatibility. gRPC prioritizes performance and efficient service-to-service communication.

🌐 REST

📄HTTP + JSON
👁️Human-readable
🖥️Browser-friendly
🔓Public APIs
{
  "user": "alex",
  "email": "alex@co.com"
}

⚡ gRPC

⚡HTTP/2 + Protobuf
📦Binary format
🚀Faster & smaller
🔧Internal services

protobuf binary

Interactive Simulations

🌐 REST

JSON · HTTP/1.1
CLIENT
SERVER

Payload

1.2KB

Latency

180ms

Serial

45ms

{"user":"alex","pass":"••••","device":"ios"}

⚡ gRPC

Protobuf · HTTP/2
CLIENT
SERVER

Payload

285B

Latency

90ms

Serial

12ms

Binary Protobuf · 285B

user: alexdevice: ios
📦

gRPC payload is 4.2× smaller for this request. Multiply that by millions of calls per day.

Solution Walkthrough

Which one should I use?

Mini Challenges

Choose REST or gRPC for each scenario.

🌍

Public Developer API

Building a public API for third-party developers. Which protocol?

🔁

50 Internal Microservices

50 microservices need to communicate efficiently at high volume.

🎮

Real-Time Multiplayer

A game needs to push state updates to players at ~30 fps.

📖

Beginner-Friendly API

An API that developers should be able to explore in a browser without any tooling.

📱

Reduce Mobile Bandwidth

Your mobile app sends thousands of small messages and bandwidth is expensive.

Monolith vs MicroservicesVertical vs Horizontal

Why this exists

REST and gRPC are both ways to move requests between components, but they optimize different things. REST prioritizes broad compatibility and easy debugging. gRPC prioritizes typed contracts, streaming, and efficient binary transport.

REST is operationally familiar

HTTP verbs, JSON, and browser tooling make REST easy to inspect and integrate across many clients and teams.

gRPC favors internal efficiency

Binary Protobuf payloads, generated clients, and streaming APIs make gRPC strong for internal service-to-service communication.

Protocol choice affects evolution

Typed schemas reduce ambiguity, but can increase coordination cost. Loose JSON is flexible, but easier to misuse over time.

Key takeaways

  • REST is usually the easier default for public APIs and browser-facing systems.
  • gRPC shines when performance, streaming, and typed contracts matter internally.
  • Payload format, tooling, and schema evolution all matter beyond raw speed.
  • Protocol choice should follow client needs, not trendiness.