CNPJValidatorV2

.NET library for validating, formatting and calculating check digits for Brazilian CNPJ numbers, including support for alphanumeric CNPJ.

GitHub NuGet Package

Overview

CNPJValidatorV2 is a lightweight .NET library designed to validate Brazilian company identification numbers (CNPJ). The library supports both the traditional numeric format and the newer alphanumeric variation.

It provides utilities for validation, sanitization, formatting and calculation of verification digits while remaining compatible with multiple .NET platforms.

Features

Validation using official CNPJ check digit rules
Support for numeric and alphanumeric CNPJ
Automatic sanitization of masked inputs
String extension methods
Unit test coverage with xUnit

Compatibility

The package targets .NET Standard 2.0, making it compatible with:

.NET Framework 4.6.1+
.NET Core
.NET 5+
.NET 6+
.NET 7+
.NET 8+
Xamarin
Mono

Example Usage

Validation


using CNPJValidatorV2.Core;

bool valid = CnpjValidator.IsValid("12.345.678/0001-95");

Sanitization


string clean = "12.345.678/0001-95".SanitizeCnpj();
// Result: 12345678000195

Formatting


string formatted = "12345678000195".FormatCnpj();
// Result: 12.345.678/0001-95

Check Digit Calculation


string cnpjWithDv = CnpjValidator.CalculateDv("12ABC34501DE");

Installation

Install via .NET CLI:


dotnet add package CNPJValidatorV2

Or via NuGet Package Manager:


Install-Package CNPJValidatorV2