fast-check is a property-based testing library for JavaScript and TypeScript.
Alternatives to ScalaCheck
ScalaCheck is a free library for checking properties of Scala and Java programs with randomized inputs. When a property fails, it reports the arguments that expose the failure. It works with sbt and integrates with ScalaTest, specs2, and LambdaTest; you can also run it with its built-in test runner. Its only external dependency is the Scala runtime, and its supported targets include JVM, Scala.js, and Scala Native. A different framework may suit you better if your tests…
Gopter is a free Go module for property-based testing.
JSVerify is a free, open-source property-based testing library for JavaScript, inspired by QuickCheck.
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Racket QuickCheck
Racket QuickCheck is a free package for testing program specifications against randomly generated inputs.
Free planLinuxmacOSWindows6.4Free plan - 5
FsCheck
FsCheck is a free library for automatically checking properties of .NET programs against randomly generated inputs.
Free planLinuxmacOSWindows6.3Free plan - 66.0Free plan
- 76.0Free plan
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PropCheck
PropCheck is a Ruby library for property-based testing: it generates inputs and checks whether assertions hold across examples.
Free planLinuxSelf-hosted5.9Free plan - 9
QuickTheories
QuickTheories is a free property-based testing library for Java 8, described as a Java version of QuickCheck.
Free planAPISelf-hosted5.9Free plan - 10
CsCheck
CsCheck is a free C# library for random testing, inspired by QuickCheck and intended for self-hosted use.
Free planSelf-hosted5.7Free plan - 11
QuickCheck
QuickCheck is a free Haskell library for testing program properties with randomly generated cases.
Free planLinux5.7Free plan - 125.7Free plan
- 135.7
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PropEr
PropEr is a free, open-source tool for automated, semi-random property-based testing of Erlang programs.
Free planSelf-hosted5.6Free plan - 15
Rantly
Rantly is a free, self-hosted Ruby library for generating random test data and running property-based checks.
Free planSelf-hosted5.6Free plan - 16
Rapid
Rapid is a Go library for property-based testing: it checks user-defined properties against test cases generated automatically.
Free planSelf-hosted5.6Free plan - 17
StreamData
StreamData is a free Elixir library for generating data and writing property-based tests with ExUnit.
Free planAPI5.6Free plan - 18
test.check
test.check is a free property-based testing tool for Clojure and ClojureScript.
Free planAPI5.6Free plan - 19
FSharp.Hedgehog
FSharp.Hedgehog is a free property-based testing system for .NET that generates inputs to help developers find edge cases.
LinuxmacOSWindows5.5 - 205.5
- 21
RapidCheck
RapidCheck is a free C++ framework for property-based testing: it generates random inputs and runs specified properties to search for cases that disprove them.
LinuxSelf-hostedWindows5.5 - 225.4
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Eris
Eris is a free, self-hosted PHP library that brings QuickCheck-style property-based testing to PHPUnit.
Self-hosted5.3 - 24

jqwik
jqwik is a free, open-source property-based testing library for JVM programmers using Java, Kotlin, or Groovy.
5.3 - 255.2
- 264.9
- 274.3
