Selenium is a great tool for automating web applications, but it lacks the ability to test the actual behavior of an application. Cucumber.js, on the other hand, is designed to teach non-programmers how to write and execute tests, and it also provides a way to define the behavior of an application. In short, Selenium is best for automating web UI testing, while Cucumber.js is best for acceptance or behavior-driven testing.
| Cucumber | Selenium |
|---|---|
| It is a Behavior Driven Development tool used to develop test cases for the behavior of software's functionality. | It is an automated testing tool. |
| Cucumber is a free or open-source BDD (Behavior Driven Development) tool. | Selenium is also a free or open-source testing tool. |
| Cucumber is a BDD-supported tool. | Selenium is a both Functional and Performance (Selenium Grid) testing tool. |
| Cucumber framework supports many languages, such as Java, Scala, Groovy, etc. beyond Ruby. | Selenium also supports many languages, such as Java, .Net, etc. |
| Cucumber includes both testers and developers to write automation steps. | Like Cucumber, Selenium also includes both testers and developers to write automation steps. |
| Cucumber is used to test only web applications. | Like Cucumber, Selenium also used to test only web applications. |
| Cucumber testing is less reliable as compared to Selenium and QTP. | The process of Selenium makes testing more reliable and dependable. |
| Cucumber works very fast in Plugin. | Selenium works slower in Plugin than Cucumber. |