FluentValidation is a popular .NET library offering a fluent, expressive interface for building strongly-typed validation rules. It supports modern .NET runtimes including .NET 8+, and integrates smoothly into .NET Core, Blazor, and other ecosystems. FluentValidation has adopted the Code of Conduct defined by the Contributor Covenant to clarify expected behavior in our community. For more information see the .NET Foundation Code of Conduct. A validation library for .NET that uses a fluent interface and lambda expressions for building strongly-typed validation rules.

Features

  • Fluent syntax for defining property validation rules (e.g., RuleFor, NotEmpty, EmailAddress)
  • Advanced features: RuleSets, cascade mode, conditional validation, collections (RuleForEach)
  • Dependency Injection support for validator classes
  • Asynchronous validation capabilities
  • Extensibility with custom validators, error codes, localization, state, severity settings
  • Integration with .NET Core and Blazor for model validation and UI enforcement

Project Samples

Project Activity

See All Activity >

Categories

Libraries

License

Apache License V2.0

Follow FluentValidation

FluentValidation Web Site

Other Useful Business Software
AI-generated apps that pass security review Icon
AI-generated apps that pass security review

Stop waiting on engineering. Build production-ready internal tools with AI—on your company data, in your cloud.

Retool lets you generate dashboards, admin panels, and workflows directly on your data. Type something like “Build me a revenue dashboard on my Stripe data” and get a working app with security, permissions, and compliance built in from day one. Whether on our cloud or self-hosted, create the internal software your team needs without compromising enterprise standards or control.
Try Retool free
Rate This Project
Login To Rate This Project

User Reviews

Be the first to post a review of FluentValidation!

Additional Project Details

Programming Language

C#

Related Categories

C# Libraries

Registered

2025-08-14