HttpClient vs RestSharp: Which One Should You Use in .NET?

When building applications in .NET that call REST APIs, the two most common tools are HttpClient and RestSharp. Both can send HTTP requests, but they differ in design, features, flexibility, and ease of use.

1. Introduction

HttpClient is a built-in .NET class for sending HTTP requests.
RestSharp is a third-party library designed to simplify REST API consumption.

2. What is HttpClient?

HttpClient is part of the .NET framework and provides low-level control for HTTP communication.

Key Points

Built into .NET
Fully customizable
Lightweight
Requires more manual coding
Best for production-level control

Example

var client = new HttpClient();
var response = await client.GetAsync("https://api.example.com/users");
var content = await response.Content.ReadAsStringAsync();

3. What is RestSharp?

RestSharp is a NuGet library that simplifies REST API calls with a cleaner, high-level interface.

Key Points

Third-party library
Easy serialization/deserialization
Cleaner request building
Less boilerplate code
Good for rapid development

Example

var client = new RestClient("https://api.example.com");
var request = new RestRequest("users", Method.Get);
var response = await client.ExecuteAsync(request);

4. Feature Comparison

Feature	HttpClient	RestSharp
Built-in	Yes	No (NuGet)
Simplicity	Moderate	Very easy
Serialization	Manual / System.Text.Json	Automatic
Request building	Manual	Fluent builder
Performance	High	Slight overhead
Control	Full	Limited compared to HttpClient
Best for	Enterprise, microservices	Quick integrations

5. Serialization & Deserialization

HttpClient: You must deserialize manually.

var data = JsonSerializer.Deserialize<User>(json);

RestSharp: Auto-deserializes into models.

var response = await client.ExecuteAsync<User>(request);

6. Request Building

HttpClient requires manually setting headers, content, methods.
RestSharp uses a fluent API:

request.AddHeader("Authorization", "Bearer xyz");
request.AddJsonBody(payload);

7. Error Handling

HttpClient: You must check status codes manually.
RestSharp: Provides a structured response with error properties.

8. When to Use What?

Use HttpClient if:

You want built-in .NET solution
You need maximum control
You work on large-scale, production services
You care about performance and dependency reduction

Use RestSharp if:

You want faster development
You work with many complex REST endpoints
You prefer built-in serialization
You want cleaner API request code

Conclusion

HttpClient is powerful, built-in, and ideal for serious production systems. RestSharp is easier and faster for rapid API integration.
Your choice depends on whether you prefer maximum control (HttpClient) or maximum convenience (RestSharp).