2nd Mar 2022

Rest API vs gRPC API


Written By, Durga Bhimani


Hello Techies,

In this Technology race nowadays API is the most common topic. Nowadays we are facing issues like “Which API is best?”, “Which API should I use?” and many more.

In this blog we are going to discuss API, its structure and comparison between API structure.

So let’s get look,

What is an API?

  • Connectivity is an amazing thing. For Now due to connectivity word became too small. In just one click we can choose, buy, pick anything from anywhere.
  • But here the main concern is, How is it possible?
    Answer is Application Programming Interface (API).
  • API is nothing but simply Messenger. Who is passing request and response between server and client. This API creates a specific determination via the internet between client and server for interacting with each other.



  • There are mainly three types of architecture for build the API:
  1. REST
  2. gRPC
  3. GraphQL

What is Rest API?

REST stands for REpresentational State Transfer.
This Architecture follows the HTTP 1.1 Model. In rest API response to be sent in JSON or XML format to the client .REST api is mostly use for CRUD (Create, Read , Update , Delete) operations. REST is commonly used GET, POST, PUT and DELETE standard method of HTTP 1.1 to get a response from the server.



What is gRPC API?

gRPC is represented for Google Remote Procedure Call.
This API structure follows HTTP 2.0 transfer protocol. But in this structure HTTP behaviour is concealed from developer as well as server and that’s lessen the complexity. Its main ambition is to make data transmission faster between microservices. By default this API Model follows the proto buffer model.

Comparison between REST vs gRPC

HTTP Protocol :

  • The RESET API follows the request-response approach of the HTTP 1.1 model. Its main disadvantage is that if a service has multiple requests at a time then the model has to handle that request and it slows down the system.
  • Whereas the gRPC API does not use the request response approach. It is by default built in the HTTP 2.0 model and It supports bidirectional and streaming communication. As gRPC is calibrated for handling multiple requests it makes service faster. It can also handle the UNARY approach same way as HTTP 1.1 approach.

Browser Support :

  • REST API is supported in almost all the browsers whereas gRPC has limitations for some browsers because all browsers do not support the HTTP 2.0 approach. It requires gRPC-web and a proxy layer to create communication between HTTP 1.1 and HTTP 2.0. Therefore gRPC is commonly used in internal or private systems.

Payload Data structure :

  • As mentiowned above, gRPC by default uses Protocol Buffer to serialize the payload. Strongly typed messages can be automatically converted from Protocol Buffer to the client and server’s programming language. And it is faster in data transmission.
  • Whereas REST is using JSON or XML format for transfer data. And Json is very famous due to its flexibility and main benefit is that it is human readable which is protocol buffer can not compete yet. But in REST API JSON formatted data first converted into programming language and then transferred .Due to this extra step transmission became slow compared to protobuf.

Code Generation :

  • gRPC has in-built code generation.
  • Where REST API uses third party tools like Postman or Swagger for code generation.

When to use gRPC vs REST?

  • As per above discussion we can say gRPC has most of the benefits but its main disadvantage is that it is Supported by rare browsers and mainly used for internal systems.
  • REST API is the most known and usable API structure. Because it is using HTTP providing support for all the browsers. It is mainly used for CRUD operation api.. But that doesn’t mean that we should neglect the gRPC API.
  • gRPC is a great way to use multi – language API. It is very fast for data transmission. And it’s mostly used in Microservices and IOT applications, we can also use this for Mobile applications because it has no limitation of browsers.


I Hope this blog cleared all your doubts about API. As we discuss API structure we can clarify that Which API structure should we use for a particular task.

Written By,

.NET Developer at Yudiz Solutions Pvt. Ltd