FluentValidation 8.5.0-preview1

A validation library for .NET that uses a fluent interface to construct strongly-typed validation rules.

Showing the top 20 packages that depend on FluentValidation.

Packages Downloads
FluentValidation.DependencyInjectionExtensions
AspNetCore integration for FluentValidation
 45
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
 43
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
 44
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
 46
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
 48
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
 3,186
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
 9,221
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
 11,504
FluentValidation.DependencyInjectionExtensions
Dependenecy injection extensions for FluentValidation
 45

FluentValidation 8 is a major release. Please read the upgrade notes at https://fluentvalidation.net/upgrading-to-8 Changes in 8.4.0: * Added simplified version of several messages across all translations to aid with ASP.NET Clientside validation. * New enum validator for string properties. Changes in 8.3.0: * Fix issue in ASP.NET Core integration with GetServiceProvider not working correctly when invoked against a CustomContext/MessageBuilderContext. * Improved how LanguageStringSource works with error-code overrides. * Fix thread-safety issue with use of PropertyValidatorOptions.Empty (now removed). * Improved how calls to When/Unless are handled internally. * DelegatingValidator is now marked as deprecated. * Improvements to Croatian language translations. * Improvements to Georgian language translations. * Resolved subtle bug where top-level WhenAsync wouldn't work correctly when wrapping a top-level call to When. Changes in 8.2.3: * Fix issue in WebApi integration where DataAnnotations validators could generate duplicate messages when in the same project as FluentValidation. Changes in 8.2.2: * Fix FluentValidation.DependencyInjection package name. Changes in 8.2.1: * Resolved issue using InjectValidator with RuleForEach. * Add support for a default IValidatorInterceptor to be registered with the ASP.NET Core Service Provider. Changes in 8.2.0: * Add extensions for injecting child validators using the ASP.NET Core Service Provider. * Implement RuleFor(...).ForEach(...) as an alternative to RuleForEach. * WithLocalizedMessage is deprecated. Use the overload of WithMessage that takes a Func instead. Changes in 8.1.3: * Resolved issue where clientside validation was incorrectly generating metadata for rules with shared conditions. * ScalePrecisionValidator now has a public method in the fluent interface. * Fix placeholder names in ScalePrecisionValidator for consistency. * Updates to Portuguese (Brazil) translations. Changes in 8.1.2: * Fix issue where shared When/Unless conditions didn't execute correctly when used with RuleForEach. Changes in 8.1.1: * Added RuleSetsExecuted property on ValidationResult. * Resolved issue introduced in 8.1 where the shared condition cache does not work correctly with RuleForEach (#970). Changes in 8.1: * Add format support in message placeholders. * Added support for overriding indexers for collection rules. * Allow error codes to be used to override localization key in the Language Manager. * Additional error details are now shown in the ShouldNotHaveValidationErrorFor test extension. * Conditions defined with root-level When/WhenAsync/Unless/UnlessAsync are now only executed once (instead of once for each rule). * Support Otherwise method chained from root-level When/WhenAsync/Unless/UnlessAsync. * Minor wording changes to default English error messages. * Japanese translation of the default error messages. * Added Skip property to MVC5's CustomizeValidatorAttribute for parity with AspNetCore and WebApi. * Remove type constraint on the OverridePropertyName overload that takes an expression. Added Skip property to MVC5's CustomizeValidatorAttribute to bring parity with AspNetCore and WebApi integration. Changes in 8.0: * Support validating only specific properties by path. * Added OnFailure method * Deprecated RuleFor(..).SetCollectionValidator in favour of RuleForEach(...).SetValidator * IStringSource.GetString now takes a validation context instead of a model instance. * Introduce PropertyValidatorOptions in order to clean up the IPropretyValidator interface. * Moved the legacy ValidatorAttribute and AttributedValidatorFactory into a separate FluentValidation.Attributes package. * Remove the pre-7.0 localization mechanism * Remove the pre-7.0 methods for custom validation * Removed many other deprecated methods Full release notes can be found at https://github.com/JeremySkinner/FluentValidation/blob/master/Changelog.txt

.NET Framework 4.5

.NET Standard 1.1

.NET Standard 1.6

.NET Standard 2.0

Version Downloads Last updated
12.1.1 1 12/08/2025
12.1.0 4 11/05/2025
12.0.0 10 05/05/2025
12.0.0-preview1 15 01/04/2025
11.12.0 5 11/06/2025
11.11.0 20 11/23/2024
11.10.0 25 09/16/2024
11.9.2 30 06/12/2024
11.9.1 30 05/04/2024
11.9.0 29 01/01/2024
11.8.1 33 11/29/2023
11.8.0 29 10/20/2023
11.7.1 32 09/05/2023
11.7.0 33 09/11/2023
11.6.0 53 08/16/2023
11.5.2 32 06/05/2023
11.5.1 32 09/11/2023
11.5.0 53 09/07/2023
11.4.0 31 03/18/2023
11.3.0 3,220 11/15/2022
11.2.2 9,233 09/14/2022
11.2.1 60 09/09/2022
11.2.0 92 08/24/2022
11.1.1 68 08/18/2022
11.1.0 99 09/08/2022
11.0.3 65 09/10/2022
11.0.2 79 08/21/2022
11.0.1 39 08/24/2022
11.0.0 39 09/08/2022
10.4.0 42 08/25/2022
10.3.6 47 07/21/2022
10.3.5 32 09/07/2022
10.3.4 61 06/27/2022
10.3.3 11,490 06/27/2022
10.3.1 49 09/09/2022
10.3.0 69 09/09/2022
10.2.3 65 09/07/2022
10.2.2 57 08/24/2022
10.2.1 38 09/03/2022
10.2.0 71 09/09/2022
10.1.0 36 08/22/2022
10.0.4 60 09/08/2022
9.5.4 60 07/03/2022
9.5.3 60 09/07/2022
9.5.2 57 09/08/2022
9.5.1 35 09/08/2022
9.5.0 59 09/08/2022
9.4.0 64 08/23/2022
9.3.0 98 09/02/2022
9.3.0-preview3 50 09/22/2022
9.3.0-preview2 73 09/21/2022
9.3.0-preview1 63 09/22/2022
9.2.2 85 09/04/2022
9.2.1 42 09/08/2022
9.2.0 60 08/21/2022
9.1.3 62 09/07/2022
9.1.2 41 08/22/2022
9.1.1 37 09/08/2022
9.1.0 40 08/22/2022
9.0.1 36 09/08/2022
9.0.0-preview5 71 10/14/2022
9.0.0-preview4 32 09/21/2022
9.0.0-preview3 44 07/03/2022
9.0.0-preview2 44 10/14/2022
9.0.0-preview1 32 09/26/2022
8.6.3 77 08/20/2022
8.6.2 36 09/02/2022
8.6.1 33 09/09/2022
8.6.0 43 09/08/2022
8.5.1 39 08/25/2022
8.5.0 41 08/25/2022
8.5.0-preview5 48 09/21/2022
8.5.0-preview4 38 09/26/2022
8.5.0-preview3 34 09/21/2022
8.5.0-preview2 37 09/21/2022
8.5.0-preview1 49 06/28/2022
8.4.0 98 09/02/2022
8.3.0 36 09/09/2022
8.2.3 42 08/25/2022
8.2.2 40 08/23/2022
8.2.1 39 09/08/2022
8.2.0 36 09/02/2022
8.1.3 43 09/07/2022
8.1.2 59 09/02/2022
8.1.1 56 09/08/2022
8.1.0 38 09/05/2022
8.1.0-preview2 80 09/22/2022
8.1.0-preview1 44 09/22/2022
8.0.101 84 09/10/2022
8.0.100 43 09/02/2022
8.0.0 43 09/02/2022
8.0.0-rc1 39 09/09/2022
8.0.0-preview4 33 09/22/2022
8.0.0-preview3 41 09/23/2022
8.0.0-preview2 43 10/14/2022
7.6.105 34 09/08/2022
7.6.104 36 09/09/2022
7.6.103 59 08/21/2022
7.6.102 32 09/08/2022
7.6.101 45 09/07/2022
7.6.100 44 09/11/2022
7.6.0 78 08/24/2022
7.6.0-preview1 33 10/14/2022
7.5.2 36 09/08/2022
7.5.1 68 07/13/2022
7.5.0 43 08/21/2022
7.4.0 56 09/07/2022
7.3.4 35 09/07/2022
7.3.3 37 09/07/2022
7.3.2 60 08/21/2022
7.3.1 40 09/07/2022
7.3.0 50 09/02/2022
7.3.0-beta3 39 09/07/2022
7.3.0-beta2 83 06/27/2022
7.3.0-beta1 37 09/03/2022
7.2.1 37 09/07/2022
7.2.0 61 08/31/2022
7.2.0-beta3 38 09/03/2022
7.2.0-beta2 35 09/08/2022
7.2.0-beta1 33 09/03/2022
7.1.1 69 09/08/2022
7.1.0 74 09/02/2022
7.1.0-beta1 30 09/02/2022
7.0.3 64 08/28/2022
7.0.2 34 09/03/2022
7.0.1 37 09/02/2022
7.0.0 60 07/21/2022
7.0.0-beta3 37 09/08/2022
7.0.0-beta2 49 08/23/2022
7.0.0-beta1 33 09/08/2022
6.4.1 36 09/07/2022
6.4.1-beta1 52 09/08/2022
6.4.0 40 09/08/2022
6.4.0-rc4 32 09/08/2022
6.4.0-rc3 65 09/04/2022
6.4.0-rc2 56 09/10/2022
6.4.0-rc1 52 09/02/2022
6.4.0-beta9 54 09/09/2022
6.4.0-beta8 39 09/12/2022
6.4.0-beta7 42 09/08/2022
6.4.0-beta6 56 09/01/2022
6.4.0-beta5 57 09/08/2022
6.4.0-beta4 43 07/18/2022
6.4.0-beta3 56 09/07/2022
6.4.0-beta2 41 08/24/2022
6.4.0-beta10 42 09/09/2022
6.4.0-beta1 34 09/14/2022
6.3.4-alpha 59 09/14/2022
6.3.3-alpha 59 09/10/2022
6.2.1 43 09/09/2022
6.2.1-beta1 49 09/08/2022
6.2.0 61 09/04/2022
6.2.0-beta1 34 09/08/2022
6.1.0 68 09/08/2022
6.0.2 36 09/09/2022
6.0.1 35 09/08/2022
6.0.0 37 09/04/2022
5.6.2 59 08/24/2022
5.6.1 71 09/03/2022
5.5.0 47 08/23/2022
5.4.0 39 09/03/2022
5.3.0 60 09/08/2022
5.2.0 64 09/09/2022
5.1.0 54 08/23/2022
5.0.0.1 38 09/09/2022
4.0.0.1 38 08/24/2022
4.0.0 45 09/02/2022
3.4.6 38 09/02/2022
3.4.0 35 08/23/2022
3.3.1 57 09/02/2022
3.2.0 61 09/07/2022
3.1.0 40 08/24/2022
3.0.0.1 58 09/08/2022
3.0.0 78 08/26/2022
2.0.0 87 08/26/2022
1.3.0 43 09/02/2022