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.AspNetCore
AspNetCore integration for FluentValidation
18
FluentValidation.AspNetCore
AspNetCore integration for FluentValidation
19
FluentValidation.AspNetCore
AspNetCore integration for FluentValidation
20
FluentValidation.DependencyInjectionExtensions
Dependency injection extensions for FluentValidation
20

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

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12.1.1 6 18.12.2025
12.1.0 11 09.11.2025
12.0.0 15 23.05.2025
12.0.0-preview1 17 12.01.2025
11.12.0 9 09.11.2025
11.11.0 20 02.12.2024
11.10.0 19 01.10.2024
11.9.2 19 12.01.2025
11.9.1 17 15.01.2025
11.9.0 21 10.01.2025
11.8.1 21 05.01.2025
11.8.0 16 15.01.2025
11.7.1 18 15.01.2025
11.7.0 19 08.01.2025
11.6.0 16 15.01.2025
11.5.2 18 08.01.2025
11.5.1 16 23.01.2025
11.5.0 19 05.01.2025
11.4.0 18 15.01.2025
11.3.0 16 09.01.2025
11.2.2 21 07.01.2025
11.2.1 17 15.01.2025
11.2.0 19 14.01.2025
11.1.1 15 07.01.2025
11.1.0 17 23.01.2025
11.0.3 15 12.01.2025
11.0.2 17 28.01.2025
11.0.1 15 12.01.2025
11.0.0 19 10.01.2025
10.4.0 16 15.01.2025
10.3.6 15 15.01.2025
10.3.5 16 15.01.2025
10.3.4 15 10.01.2025
10.3.3 16 15.01.2025
10.3.1 22 10.01.2025
10.3.0 17 12.01.2025
10.2.3 21 15.01.2025
10.2.2 17 15.01.2025
10.2.1 17 15.01.2025
10.2.0 16 15.01.2025
10.1.0 16 15.01.2025
10.0.4 18 15.01.2025
9.5.4 17 15.01.2025
9.5.3 17 15.01.2025
9.5.2 17 14.01.2025
9.5.1 24 10.01.2025
9.5.0 21 15.01.2025
9.4.0 20 10.01.2025
9.3.0 16 10.01.2025
9.3.0-preview3 15 10.01.2025
9.3.0-preview2 16 09.01.2025
9.3.0-preview1 18 19.02.2025
9.2.2 17 10.01.2025
9.2.1 16 09.01.2025
9.2.0 24 15.01.2025
9.1.3 16 15.01.2025
9.1.2 17 15.01.2025
9.1.1 19 10.01.2025
9.1.0 20 10.01.2025
9.0.1 19 14.01.2025
9.0.0-preview5 16 06.01.2025
9.0.0-preview4 18 07.01.2025
9.0.0-preview3 18 06.01.2025
9.0.0-preview2 20 07.01.2025
9.0.0-preview1 17 12.01.2025
8.6.3 19 15.01.2025
8.6.2 17 15.01.2025
8.6.1 18 15.01.2025
8.6.0 17 15.01.2025
8.5.1 18 15.01.2025
8.5.0 17 15.01.2025
8.5.0-preview5 20 10.01.2025
8.5.0-preview4 15 11.01.2025
8.5.0-preview3 16 10.01.2025
8.5.0-preview2 15 06.01.2025
8.5.0-preview1 17 10.01.2025
8.4.0 16 28.01.2025
8.3.0 16 10.01.2025
8.2.3 26 15.01.2025
8.2.2 17 05.01.2025
8.2.1 16 28.01.2025
8.2.0 17 15.01.2025
8.1.3 17 15.01.2025
8.1.2 15 12.01.2025
8.1.1 17 10.01.2025
8.1.0 16 14.01.2025
8.1.0-preview2 17 13.01.2025
8.1.0-preview1 17 23.01.2025
8.0.101 16 10.01.2025
8.0.100 21 15.01.2025
8.0.0 17 15.01.2025
8.0.0-rc1 16 10.01.2025
8.0.0-preview4 16 05.01.2025
8.0.0-preview3 19 07.01.2025
8.0.0-preview2 18 07.01.2025
7.6.105 17 15.01.2025
7.6.104 16 15.01.2025
7.6.103 17 15.01.2025
7.6.102 19 11.01.2025
7.6.101 20 15.01.2025
7.6.100 19 15.01.2025
7.6.0 19 12.01.2025
7.6.0-preview1 15 07.01.2025
7.5.2 16 10.01.2025
7.5.1 17 15.01.2025
7.5.0 17 15.01.2025
7.4.0 17 15.01.2025
7.3.4 20 10.01.2025
7.3.3 17 15.01.2025
7.3.2 18 15.01.2025
7.3.1 16 15.01.2025
7.3.0 17 15.01.2025
7.3.0-beta3 15 28.01.2025
7.3.0-beta2 16 28.01.2025
7.3.0-beta1 16 28.01.2025
7.2.1 18 09.01.2025
7.2.0 16 15.01.2025
7.2.0-beta3 18 28.01.2025
7.2.0-beta2 15 27.01.2025
7.2.0-beta1 16 28.01.2025
7.1.1 20 10.01.2025
7.1.0 21 15.01.2025
7.1.0-beta1 19 10.01.2025
7.0.3 17 15.01.2025
7.0.2 16 28.01.2025
7.0.1 20 10.01.2025
7.0.0 17 15.01.2025
7.0.0-beta3 23 13.01.2025
7.0.0-beta2 23 10.01.2025
7.0.0-beta1 17 15.01.2025
6.4.1 18 28.01.2025
6.4.1-beta1 15 28.01.2025
6.4.0 23 10.01.2025
6.4.0-rc4 18 10.01.2025
6.4.0-rc3 24 10.01.2025
6.4.0-rc2 18 10.01.2025
6.4.0-rc1 16 10.01.2025
6.4.0-beta9 17 10.01.2025
6.4.0-beta8 15 28.01.2025
6.4.0-beta7 16 07.01.2025
6.4.0-beta6 22 07.01.2025
6.4.0-beta5 16 28.01.2025
6.4.0-beta4 17 13.01.2025
6.4.0-beta3 16 28.01.2025
6.4.0-beta2 15 27.01.2025
6.4.0-beta10 15 07.01.2025
6.4.0-beta1 16 29.01.2025
6.3.4-alpha 16 10.01.2025
6.3.3-alpha 16 10.01.2025
6.2.1 17 28.01.2025
6.2.1-beta1 15 27.01.2025
6.2.0 16 28.01.2025
6.2.0-beta1 16 07.01.2025
6.1.0 20 07.01.2025
6.0.2 21 11.01.2025
6.0.1 16 24.01.2025
6.0.0 16 28.01.2025
5.6.2 18 10.01.2025
5.6.1 17 15.01.2025
5.5.0 16 15.01.2025
5.4.0 17 15.01.2025
5.3.0 17 15.01.2025
5.2.0 17 15.01.2025
5.1.0 20 10.01.2025
5.0.0.1 19 15.01.2025
4.0.0.1 17 10.01.2025
4.0.0 15 23.01.2025
3.4.6 18 14.01.2025
3.4.0 17 15.01.2025
3.3.1 18 15.01.2025
3.2.0 14 15.01.2025
3.1.0 20 10.01.2025
3.0.0.1 18 15.01.2025
3.0.0 17 15.01.2025
2.0.0 17 28.01.2025
1.3.0 19 10.01.2025